f(x) = 2x + 9
f^-1(x)= ??

Answers

Answer 1

Step-by-step explanation:

Given

f(x) = 2x + 9

f^-1 (x) = ?

Let

y = f(x)

y = 2x + 9

Interchanging the roles of x and y we get

x = 2y + 9

2y = x - 9

y = ( x - 9) / 2

Therefore

⏩f^-1(x) = (x-9)/2

Hope it will help :)


Related Questions

How do I solve this. Y=f(x)+a moves the function

Answers

Answer:

up

Step-by-step explanation:

for linear functions, adding a constant will increase the y value by two and shift the line up two units on the graph.

Answer: It moves the function 'a' units up if a > 0. Or it moves the function |a| units down if a < 0.

Explanation:

Consider an example like y = f(x)+2. This shifts the f(x) curve 2 units up because we're adding 2 to each y or f(x) output. A point like (5,7) shifts up to (5,9).

As another example, y = f(x)-5 moves the curve 5 units down.

In the first example, we had a > 0 which moved the function 'a' units up (a = 2 in that case). The second example had a = -5 which means a < 0, so that's why we shifted |a| = |-5| = 5 units down.

Multiply and show work

Answers

Answer:

-15m^10 -38m8+57m^6+98m^4-30m^2

Answer:

jere is your answer i hope it will help u

solve the following by factolisation formula
1. x(2x+1)=0
2.4xsquere-11-3x=0​

Answers

1.

X = 0

2x + 1 = 0

X = 0

X = - ½ (Because we brought the numbers from one side to the other)

2.

Not sure for number 2.

1. x(2x+1)=0
It means x=0 or 2x+1=0. So
x=0

2x+1=0
2x=-1
x=-1/2


2.

➡️. 4x^2-3x-11=0
(It must take the form of ax^2+bx+c=0)

4x^2-3x=11
➡️ 4x^2-3x+9/4=11+9/4 ( you take the half of the number of 3 from 3x and square it. The half of 3 is 3/2 and when you square it becomes 9/4.)

➡️ 4x^2-3x+9/4=31/4

➡️. [4x^2-3/2]=31/4
( You put 9/4 in square root first. That means 3/2. since 3x is negative you also take negative for 3/2.)

➡️ 4x^2-3/2= positive or negative 31/4.

➡️. 4x^2=31/4+3/2

➡️. 4x^2= 37/4

➡️. x^2= 37/8

➡️. x= the square root of 37/8



Chef Amy does beginning inventory on Thursday night and finds that she has $4697 in food products in the restaurant
Throughout the week she purchases:
$668 produce
$2206 meat
$2488 dry goods
$3755 dairy
The following Thursday she does ending inventory and finds that she has $3518 in food.
She looks at her sales and finds that she made $30658 over the same 7 day period.
What is her food cost as a percentage of sales (her food cost percentage)? Please input your answer as a percentage (30%), instead of a decimal (0.3).

Answers

Answer:

Her food cost as a percentage of sales is 33.58%.

Step-by-step explanation:

Since Chef Amy does beginning inventory on Thursday night and finds that she has $ 4697 in food products in the restaurant, and throughout the week she purchases:

$ 668 produces

$ 2206 meat

$ 2488 dry goods

$ 3755 dairy

The following Thursday she does ending inventory and finds that she has $ 3518 in food.

She looks at her sales de ella and finds that she made $ 30658 over the same 7 day period.

To determine what her food cost is as a percentage of sales (her food cost percentage), the following calculation must be performed:

4,697 + 668 + 2,206 + 2,488 + 3,755 = 13,814

13,814 - 3,518 = 10,296

30,658 = 100

10,296 = X

10,296 x 100 / 30,658 = X

1,029,600 / 30,658 = X

33.58 = X

Therefore, her food cost as a percentage of sales is 33.58%.

What is the value of y?

Enter your answer, as an exact value, in the box.

Answers

Answer:

y=4√3 units

Step-by-step explanation:

Hi there!

We are given ΔABC, which is a right triangle (m<C=90°), m<A=60°, AB=8, and BC=y

We need to find the value of y (BC)

The side AB is the hypotenuse of the  (the side opposite from the right angle).

BC is a leg, which is a side that makes up the right angle.

Now, if we have a right triangle that has one of the acute angles as 60°, the side OPPOSITE from that 60° angle (in this case, BC) is equal to [tex]\frac{a\sqrt{3}}{2}[/tex], where a is the length of the hypotenuse

Since we have the hypotenuse given as 8, the length of BC (y) is [tex]\frac{8\sqrt{3}}{2}[/tex], or 4√3

so y=4√3 units

Hope this helps!

سا (a) From the definition of derivatives determine dy÷dx if y = -2÷x​

Answers

Step-by-step explanation:

Given: [tex]y = -\dfrac{2}{x}[/tex]

Derivative of a power function [tex]x^n[/tex]:

[tex]\dfrac{d}{dx}(x^n) = nx^{n-1}[/tex]

Therefore,

[tex]\dfrac{dy}{dx}=-2(-1)x^{-2} = \dfrac{2}{x^2}[/tex]

Working to
(simplify y
Lisa, an experienced shipping clerk, can fill a certain order in 7 hours, Bill, a new clerk, needs 9 hours to do the
same job. Working together, how long will it take them to fill the order?

Answers

it might take 19 hours i might be wrong

Step-by-step explanation:

Please help me i will give you brainlest

Answers

Answer:

x = 14/3

Step-by-step explanation:

9.

The given equation is:

(x-2)+(x-3)+(x-9)=0

After opening the brackets,

x-2+x-3+x-9=0

3x+(-2-3-9) = 0

3x-14=0

x = 14/3

So, the value of x is equal to 14/3.

if a x + B Y is equal to a square minus b square and b x + A Y is equal to zero find the value of x + Y

Answers

9514 1404 393

Answer:

  a-b

Step-by-step explanation:

Add the two equations together:

  (ax +by) +(bx +ay) = (a² -b²) +(0)

  x(a +b) +y(a +b) = (a +b)(a -b)

  x + y = a - b . . . . . divide by (a+b), assuming a+b ≠ 0

the difference when a number doubled is subtracted from 3​

Answers

Answer: Let the number be x

3-2x is the equation.

In a pen of goats and chickens, there are 40 heads. and 130 feet How many goats and chickens are there?​

Answers

Answer:

25 goat and 15 chicken

Step-by-step explanation:

Say the number of goats is G, then the number of chickens is 40 - G as there are 40 heads and each chicken and each goat has one head.

The number of feet is 130

So 2(40 - G) + 4G = 130

So 80 - 2G + 4G = 130

2G = 50

G = 25

25 goats and 15 chickens

HELP PLEASE!!! So for this problem is got 0.48 however I just wanted to confirm that my answer is correct. Can someone please help me if the answer is wrong and how to solve it. Thank your for your time

Answers

Answer:

ur answer is correct

A =xy

A = 1.6×0.3 = 0.48

Question 8
Points 3
Identify the functions whose lines are parallel.
0 3x + 2y = 45 and 8x + 4y = 135
x + y = 25 and 2x + y = 15
O 2x + 2y = 50 and 4x + 2y = 90
O 2x + 2y = 4 and 4x + 4y = 16

Answers

Answer:

2x + 2y = 4 and 4x + 4y = 16

Step-by-step explanation:

For two lines to be parallel, they must have the same slope.

To determine the correct answer to the question, we shall determine the slope of each equation in the given options to see which have the same slope. This can be obtained as follow:

1st option:

3x + 2y = 45 and 8x + 4y = 135

We shall rearrange the above equations to look like y = mx + c

NOTE: m is the slope.

3x + 2y = 45

rearrange

2y = –3x + 45

Divide both side by 2

y = –3x/2 + 45/2

Slope (m) = –3/2

8x + 4y = 135

Rearrange

4y = –8x + 135

Divide both side by 4

y = –8x/4 + 135/4

Slope (m) = –8/4 = –2

The two equation has different slopes. Thus, they are not parallel.

2nd option:

x + y = 25 and 2x + y = 15

x + y = 25

Rearrange

y = –x + 25

Slope (m) = –1

2x + y = 15

Rearrange

y = –2x + 15

Slope (m) = –2

The two equations has different slopes. Thus, they are not parallel.

3rd option:

2x + 2y = 50 and 4x + 2y = 90

2x + 2y = 50

Rearrange

2y = –2x + 50

Divide both side by 2

y = –2x/2 + 50/2

Slope (m) = –2/2 = –1

4x + 2y = 90

Rearrange

2y = –4x + 90

Divide both side by 2

y = –4x/2 + 90/2

Slope (m) = –4/2 = –2

The two equations has different slopes. Thus, they are not parallel.

4th option:

2x + 2y = 4 and 4x + 4y = 16

2x + 2y = 4

Rearrange

2y = –2x + 4

Divide both side by 2

y = –2x/2 + 4/2

Slope (m) = –2/2 = –1

4x + 4y = 16

Rearrange

4y = –4x + 16

Divide both side by 4

y = –4x/4 + 16/4

Slope (m) = –4/4 = –1

The two equations have the same slopes. Thus, they are parallel.

A​ single, six-sided die is rolled. Find the probability of rolling an even number or a number less than 6 .

Answers

Answer:

P=1

Step-by-step explanation:

P(even or less than 6) = P(even)+P(less than 6) -P(even ∩ less than 6)

P(even)=3/6 (numbers 2,4, and 6)

P(less than 6) =5/6 (numbers 1,2,3,4, and 5)

P(even ∩ less than 6)=2/6 (numbers 2 and 4)

(3/6)+(5/6) -(2/6) = (3+5-2)/6 = 6/6=1

in a class of 38 student,30 are good in mathematics and 22 are good in physics how many students are good in both mathematics and physics

Answers

Answer:

8 are bad in math and 16 in physics

Step-by-step explanation:

A bank gives you a loan of 1,500,000 Baht to buy a house. The interest rate of the loan is 0.01% per day (Using 1 year = 365 days) How much interest you pay after 10 years

Answers

Answer:

547 500

Step-by-step explanation:

Interest for 1 year:

0.01%×365=3.65 a year

3.65×10=36.5% for 10 years

36.5×1,500,000÷100=547 500

The interest paid after 10 years is 547 ,500 Baht.

What is Interest ?

Interest is the amount paid or earned when a loan is taken or an investment is done respectively.

It is given that

Principal = 1,500,000 Baht

Rate = 0.01 % per day

Time period = 10 years

Interest = ?

Interest = P *R *T/100

Interest = 1500000 * 0.01 *365* 10 / 100

Interest = 547,500 Baht

Therefore the interest paid after 10 years is 547 ,500 Baht.

To know more about Interest

https://brainly.com/question/13324776

#SPJ2

aulo uses an instrument called a densitometer to check that he has the correct ink colour.

For this print job the acceptable range for the reading on the densitometer is 1.8 ± 10%.

What is the acceptable range for the densitometer reading?

Answers

Answer:

The range is from 1.62 to 1.98.

Step-by-step explanation:

We have to solve for the percentage of the particular value if the range of the answer should be +/- 10% of the particular value.

The value given is 1.8, we thus want to find 10% of that: 1.8 * 10/100 = 0.18

Then, add this value to the original value of 1.8: 1.8+0.18 = 1.98

Furthermore, subtract .18 from from the original value of 1.8: 1.8-0.18 = 1.62

The range will be between these two numbers, so the range is from 1.62 to 1.98.

The following figure appears in a math workbook. Students are asked to reflect the polygon across the line, then rotate it 90 degrees clockwise . Which figure shows the result of the two transformations?

Answers

Answer:

C

Step-by-step explanation:

tracing paper is your friend

The mean incubation time of fertilized eggs is 19 days. Suppose the incubation times are approximately normally distributed with a standard deviation of 1 day. Answer the following. For each question draw an appropriate distribution function​ (graph) to represent the​ data, shade the desired area, and show all​ work, including what you input into your calculator to attain your results.
(A) The 14th percentile for incubation times is __ days.
(B) The incubation times that make up the middle 97% of fertilized eggs are __ to __ days.

Answers

Answer:

a)17.92

b) 16.83 .... 21.17

Step-by-step explanation:

ρ→   z

0.14 = -1.080319341

-1.080 = (x - 19)/1 = 17.92

~~~~~~~~~~~~~~~~~~

3% / 2 = 1.5%

1.5% - 98.5%

ρ→   z

0.015 = -2.170090378 ....  -2.17 = (x-19) =16.83

0.985 = 2.170090378  ....   2.17 = (x-19) =21.17

70. If set A consists of (3, 5, 7, 9) and set B consists of (1, 2, 3, 5, 8, 13), what is the average of the union of set A and set B?

A) 6
B) 3
C) 48
D) 56

⚠️will give brainliest to the best answer

Answers

Step-by-step explanation:

the answer would be 6. brrr

A) 6

{1,2,3,5,7,8,9,13}

The average is going to be 6.

Is the random variable described discrete or continuous? The amount of rain during the next thunderstorm.

Answers

Answer:

continuous

rain does not fall in specific units like 1 inch , 2 inches etc... but 1.23456 etc..

Step-by-step explanation:

Using law of sines please show process!!!

Answers

Let the <C=x

We know in a triangle

☆Sum of angles=180°

[tex]\\ \sf\longmapsto 51+26+x=180[/tex]

[tex]\\ \sf\longmapsto 77+x=180[/tex]

[tex]\\ \sf\longmapsto x=180-77[/tex]

[tex]\\ \sf\longmapsto x=103°[/tex]

a certain number n is 6 more than a second number and 9 less than a third number. in terms of n, which of the following expressions represents the second number

Answers

Answer:

n-6

Step-by-step explanation:

it is given that the first number is n

for the second number:

n is 6 more than a second number

more than means that we should subtract n by 6 to get the second number since n is 6 more than the second number

second number: n-6

A candy company fills a package of candy with individually wrapped pieces of candy. The number of pieces of candy per package varies because the package is sold by weight. The company wants to estimate the number of pieces per package. Inspectors randomly sample 120 packages of this candy and count the number of pieces in each package. They find that the sample mean number of pieces is 18.72. Assume the population standard deviation of .8735. What is the point estimate of number of pieces per package

Answers

Answer:

The point estimate for the number of pieces per package is of 18.72.

Step-by-step explanation:

Point estimate of a population mean:

The mean of the sample gives an estimate for the population mean.

They find that the sample mean number of pieces is 18.72.

This means that the point estimate for the number of pieces per package is of 18.72.

A telephone exchange operator assumes that 9% of the phone calls are wrong numbers. If the operator is correct, what is the probability that the proportion of wrong numbers in a sample of 448 phone calls would differ from the population proportion by more than 3%

Answers

Answer:

0.0264 = 2.64% probability that the proportion of wrong numbers in a sample of 448 phone calls would differ from the population proportion by more than 3%

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]

A telephone exchange operator assumes that 9% of the phone calls are wrong numbers.

This means that [tex]p = 0.09[/tex]

Sample of 448

This means that [tex]n = 448[/tex]

Mean and standard deviation:

[tex]\mu = p = 0.09[/tex]

[tex]s = \sqrt{\frac{p(1-p)}{n}} = \sqrt{\frac{0.09*0.91}{448}} = 0.0135[/tex]

What is the probability that the proportion of wrong numbers in a sample of 448 phone calls would differ from the population proportion by more than 3%?

More than 9% + 3% = 12 or less than 9% - 3% = 6%. Since the normal distribution is symmetric, these probabilities are the same, so we find one of them and multiply by 2.

Probability it is less than 6%

P-value of Z when X = 0.06. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

By the Central Limit Theorem

[tex]Z = \frac{X - \mu}{s}[/tex]

[tex]Z = \frac{0.06 - 0.09}{0.0135}[/tex]

[tex]Z = -2.22[/tex]

[tex]Z = -2.22[/tex] has a p-value of 0.0132

2*0.0132 = 0.0264

0.0264 = 2.64% probability that the proportion of wrong numbers in a sample of 448 phone calls would differ from the population proportion by more than 3%

\int (x+1)\sqrt(2x-1)dx

Answers

Answer:

[tex]\int (x+ 1) \sqrt{2x-1} dx = \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{15}(2x-1)^{\frac{5}{2}} + C[/tex]

Step-by-step explanation:

[tex]\int (x+1)\sqrt {(2x-1)} dx\\Integrate \ using \ integration \ by\ parts \\\\u = x + 1, v'= \sqrt{2x - 1}\\\\v'= \sqrt{2x - 1}\\\\integrate \ both \ sides \\\\\int v'= \int \sqrt{2x- 1}dx\\\\v = \int ( 2x - 1)^{\frac{1}{2} } \ dx\\\\v = \frac{(2x - 1)^{\frac{1}{2} + 1}}{\frac{1}{2} + 1}} \times \frac{1}{2}\\\\v= \frac{(2x - 1)^{\frac{3}{2}}}{\frac{3}{2}} \times \frac{1}{2}\\\\v = \frac{2 \times (2x - 1)^{\frac{3}{2}}}{3} \times \frac{1}{2}\\\\v = \frac{(2x - 1)^{\frac{3}{2}}}{3}[/tex]

[tex]\int (x+1)\sqrt(2x-1)dx\\\\ = uv - \int v du[/tex]                              

[tex]= (x +1 ) \cdot \frac{(2x - 1)^{\frac{3}{2}}}{3} - \int \frac{(2x - 1)^{\frac{3}{2}}}{3} dx \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ [ \ u = x + 1 => du = dx \ ][/tex]    

[tex]= \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{3} \int (2x - 1)^{\frac{3}{2}}} dx\\\\= \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{3} \times ( \frac{(2x-1)^{\frac{3}{2} + 1}}{\frac{3}{2} + 1}) \times \frac{1}{2}\\\\= \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{3} \times ( \frac{(2x-1)^{\frac{5}{2}}}{\frac{5}{2} }) \times \frac{1}{2}\\\\= \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{15} \times (2x-1)^{\frac{5}{2}} + C\\\\[/tex]

What is the slope of (-1,3) and (3,1)

Answers

Answer:   -1/2

Work Shown:

Apply the slope formula

m = (y2-y1)/(x2-x1)

m = (1-3)/(3-(-1))

m = (1-3)/(3+1)

m = -2/4

m = -1/2 is the slope

In decimal form, this converts to -0.5, though usually slopes are in fraction form.

Melanie has D dimes and Q quarters. She has no less than $4 worth of coins altogether. Write this situation as an inequality.

Answers

Step-by-step explanation:

D(.10) + Q(.25) = 4

I think

Answer:

D(.10) + Q(.25) = 4

Step-by-step explanation:

Sally bought five books.Their mean price was 3.25. The total cost for four books was 11.75.what was the cost of the fifth book​

Answers

Answer:

$4.50

Step-by-step explanation:

Use the mean formula: mean = sum of elements / number of elements

Let x represent the cost of the fifth book, and solve for x:

mean = sum of elements / number of elements

3.25 = (11.75 + x) / 5

16.25 = 11.75 + x

4.5 = x

So, the cost of the fifth book was $4.50

The proportion of brown M&M's in a milk chocolate packet is approximately 14% (Madison, 2013). Suppose a package of M&M's typically contains 52 M&M's

Answers

Answer:

7 brown M&Ms.

Step-by-step explanation:

This question is not complete, but I will assume that the final question is how many brown M&Ms will be in this package.

0.14 × 52 is our equation.

The answer is 7.28. We cannot have .28 of a brown M&M in a package (unless you count the broken ones) so there will be, on average, 7 brown M&Ms in a package.

(again, the question is incomplete, so this may not be the answer)

Other Questions
f a business wants to sell a product or service on the Internet for the first time, the __________ would need to understand the wide-ranging risks involved as well as the organization's security capability. A. executive committee B. operational risk committee C. compliance committee D. security committee Pablo, whose mass is 60 kg, is moving along at a velocity of 8 m/s. How much kinetic energy does he have? -10ab(13c) what is the answer PLEASE HELPPPP WILL GIVE BRAINLIESTTTTFactor the following expressions completely. Show and check all work on your own paper.9x2-18x+9 What is established by Article 3 of the Constitution?A. Judicial BranchB. Executive BranchC. Legislative Branch Nu nhng kh khn trong vic kinh doanh sn phm du lch v bin php khc phc chng. When writing a speech for a Public Speaking course, it is important to:(AUnderstand the occasion and think about your topic.B Consider your audience and get them involved.C Outline your speech, use visuals and prompters, and make sure to practice to stay within the time limitD-All responses provided. Which two parts of this excerpt from Christopher Marlowes The Tragical History of Doctor Faustus bring out the theme of forbidden knowledge? CHORUS: Cut is the branch that might have grown full straight,And burned is Apollo's laurel bough,That sometime grew within this learned man.Faustus is gone; regard his hellish fall,Whose fiendful fortune may exhort the wiseOnly to wonder at unlawful things,Whose deepness doth entice such forward wits To practise more than heavenly power permits plz help ASAP on my final project I will give you20$ Given the code as follows: main() { int i = 3, n; float x; x = i; n = 8 % x; } What problem will occur? Group of answer choices A compilation error will occur. A run time error will occur. An inheritance error will occur. No problem will occur at all. Popular mixed drinks such as margaritascontain more alcohol than a standard drink.A. willB. do not necessarilyO C. neverDrugsthe chemistry of the brain and the way that a person thinks.A. changeB. don't changeC. trickHighway Safety Administration Which of the following is a similarity between the two pieces of writing?A. Both authors devote an entire paragraph to their hook.B. Both authors use chronological organization.C. Both authors discuss that the writer is key.D. Both authors allude to Charles Dickens. Apes went extinct in southern Europe (including France, Spain, Italy, and Greece) during the late Miocene, probably as a result of Q. Compared with other investment asset classes, an investment in real estate is least likely to be characterized by: How many atoms in each elemental sample? 4.9 mol Cu 5.410^-3 Mol C24.0 Mol Hg 0.160 mol Na The thickness X of aluminum sheets is distributed according to the probability density function f(x) = 450 (x2 - x) if 6 < x < 12 0 otherwise 5-1 Derive the cumulative distribution function F(x) for 6 < x < 12. The answer is a function of x and is NOT 1! Show the antiderivative in your solution. 5-2 What is E(X) = {the mean of all sheet thicknesses)? Show the antiderivative in your solution. The ocean surface is at 0 ft elevation. A diver is underwater at a depth of 138 ft. In this area, the ocean floor has a depth of 247 ft. A rock formation rises to a peak 171 ft above the ocean floor. How many feet below the top of the rock formation is the diver? How many alkenes are formed by E2 elimination of HBr from 3-bromo -3,4-dimethylhexane using a strong base such as sodium methoxide (NOTE: draw 3,4-dimethyl as anti configuration) Lipids and carbohydrates have many functions in the body of an organism. Specific lipids and proteinsperform specific tasks. Read the descriptions below to answer the following question: How aretriglycerides and glycogen similar in their primary function? A. Both act as catalysts.B. Both store genetic information for the organism.C. Both support the structure of the organism.D. Both store energy used by the organism. Would you kindly help me.Im having a hard time understanding and I've been crying a lot trying to understand it