Find the interval in which f(x) = 3x2 - 2x is decreasing.

Answer:

x=4

y=7

Step-by-step explanation:

12=3x

x=4

6=y-1

y=6+1

y=7

Answer:

x=4

Step-by-step explanation:

==========================================================

Explanation:

area of rectangle = L*W = 129

L*W = 129

x*(2x-9) = 129

2x^2-9x = 129

2x^2-9x-129 = 0

Apply the quadratic formula. We'll use a = 2, b = -9, c = -129.

[tex]x = \frac{-b\pm\sqrt{b^2-4ac}}{2a}\\\\x = \frac{-(-9)\pm\sqrt{(-9)^2-4(2)(-129)}}{2(2)}\\\\x = \frac{9\pm\sqrt{1113}}{4}\\\\x \approx \frac{9\pm33.36165464}{4}\\\\x \approx \frac{9+33.36165464}{4}\ \text{ or } \ x \approx \frac{9-33.36165464}{4}\\\\x \approx \frac{42.36165464}{4}\ \text{ or } \ x \approx \frac{-24.36165462}{4}\\\\x \approx 10.59041366\ \text{ or } \ x \approx -6.09041364\\\\[/tex]

We ignore the negative solution because a negative length makes no sense.

The length is approximately L = 10.5904 cm.

The width is 2L-9 = 2*10.5904-9 = 12.1808 cm approximately.

As a quick check,

L*W = 10.5904*12.1808 = 128.99954432

which isn't too far off from 129. We have rounding error which is why we don't perfectly land on the target area value. If you wanted to get closer to the value 129, then use more decimal digits in the approximations of L and W.

----------------------------

If you draw a diagonal in the rectangle, then you form two identical or congruent right triangles.

Focusing on one of those triangles, we have

Apply the pythagorean theorem

a^2+b^2 = c^2

c = sqrt( a^2 + b^2 )

c = sqrt( (10.5904)^2 + (12.1808)^2 )

c = 16.1408940520653

c = 16.14

The diagonal is roughly 16.14 cm long.

Answer:

3(x + 8)

Step-by-step explanation:

"The product of three and the sum of a number and eight".

First, note that:

1) Product means multiply.

2) Sum means addition.

With that in mind, also note the order of operations. The order of operations is defined as PEMDAS, or:

Parenthesis

Exponents (& Roots)

Multiplication

Division

Addition

Subtraction

Also, let "a number" be denoted as the variable, x.

~

Firstly, "the sum of a number and eight": x + 8

Next, "The product of...": 3 *

Putting the two parts together will generate: 3(x + 8)

3(x + 8) is your answer.

~

Answer:

33%

Step-by-step explanation:

$16,500-$11,055= $5,445

$5,445÷$16,500= 0.33 which in percentage format is 33%

HOPE THIS HELPS! MARK BRAINLIEST PLEASE!!!!!

Answer:

b + 5; when b = 3.4 the distance Sandra rode is 17 miles.

Step-by-step explanation:

Answer:

Step-by-step explanation:

The question has an error. Volume is expressed in cubic units. You probably mean cm³ .

Volume = 8 cm³

Length of each edge = ∛8 = 2 cm

Answer:

2cm

Step-by-step explanation:

Volume of cube=a^3 cubic units

8=a^3

a=cuberoot of 8

which is 2

Answer:

Determination of type of error arising from the situations

Situation       Type of Error

1.                    Nonresponse

2.                   Bad sampling method

3.                   Question wording

4.                   Undercoverage

Step-by-step explanation:

Types of errors:

a. question wording means that the manner a question is worded elicits some particular responses, which may not accurately reflect reality.

b. undercoverage occurs when some elements of the target population is not represented on the survey frame.

c. processing error arises from data processing

d. bad sampling method is caused by the voluntariness of those who choose to respond.

e. response error is caused by a questionnaire that requires framing improvements, misinterpretation of questions by interviewers or respondents, and errors in respondents' statements.

f. nonresponse error arises as a result of incomplete information or partial response.

g. random sampling error arises from the limited sample size when compared with the population size.

Answer:

no solution

Step-by-step explanation:

multiply 2 and get 2x^2+18-4=0

combine like terms

2x^2+14=0

subtract 14

2x^2=-14

there can't be a square root of a negative number so there's no solution

Answer:

x = ±i sqrt(7)

Step-by-step explanation:

2(x^2+9)-4=0

Add 4 to each side

2(x^2+9)-4+4=0+4

2(x^2+9)=4

Divide by 2

2(x^2+9)/2=4/2

(x^2+9)=2

Subtract 9 from each side

x^2 +9-9 = 2-9

x^2 = -7

Taking the square root of each side

sqrt(x^2) =sqrt(-7)

x = sqrt(-1 *7)

x = ±i sqrt(7)

9514 1404 393

Answer:

  1

Step-by-step explanation:

The slope is given by the formula ...

  slope = (y2 -y1)/(x2 -x1)

  slope = (5 -4)/(3 -2) = 1/1 = 1

The slope of MN is 1.

__

Dilation does not change the slope.

The length of CV is 5 units

The length of C’V’ is 7.5 units

The scale factor is 7.5 / 5 = 1.5

Answer: 1.5

Answer:

3rd option

Step-by-step explanation:

(1/2)^-2t

= (2^-1)^-2t

= 2^2t

= (2^2)^t

Answered by GAUTHMATH

Answer:

[tex]y=4x[/tex]

Answer:

y = -4x

hope that helped.........

The identity as been verified/proved as:

[tex]1 - \tan\ a\ tan\ b = 1 - \tan\ a\ tan\ b[/tex]

Given that:

[tex]\frac{\cos(a + b)}{\cos\ a\cos b} = 1 - \tan\ a\ tan\ b[/tex]

Apply cosine identity to the numerator

[tex]\frac{\cos\ a\ cos\ b - \sin a\ sin\ b}{\cos\ a\cos b} = 1 - \tan\ a\ tan\ b[/tex]

Split the fraction:

[tex]\frac{\cos\ a\ cos\ b}{\cos\ a\cos b} - \frac{\sin a\ sin\ b}{\cos\ a\cos b} = 1 - \tan\ a\ tan\ b[/tex]

Cancel out common terms

[tex]1 - \frac{\sin a\ sin\ b}{\cos\ a\cos b} = 1 - \tan\ a\ tan\ b[/tex]

In trigonometry, we have:

[tex]\frac{\sin \theta}{\cos \theta} = \tan \theta[/tex]

So, the equation becomes:

[tex]1 - \tan\ a\ tan\ b = 1 - \tan\ a\ tan\ b[/tex]

Hence, the identity has been verified

Read more about trigonometry identities at:

https://brainly.com/question/21055284

Answer:

15

Step-by-step explanation:

The figure has total 15 faces, the correct option is A.

A hexagon is a polygon with six sides.

A hexagonal pyramid has 8 faces

From (2 hexagonal base + 6 lateral surfaces)

A hexagonal prism has 7 faces

From ( A hexagonal base + 6 lateral faces)

Total faces the figure has is 8 +7 = 15

To know more about Hexagon

https://brainly.com/question/3295271

#SPJ5

..... Here

This is the answer

Answer:

a) 25/35

b) 30/42

Step-by-step explanation:

a)

Variable x = denominator if numerator is 25

5/7 = 25/x

5 × x = 7 × 25

5x = 175

x = 35

b)

Variable y = numerator if denominator is 42

5/7 = y/42

5 × 42 = 7 × y

210 = 7y

30 = y

25/35

30/42

To get 25/35 multiply by 5

To get 30/42 multiply by 6

Answer:

Step-by-step explanation:

Garden is two times as long as it is wide.

L = 2W

Perimeter is 120 feet

2L + 2W = 120

L +W = 60

(2W) + W = 60

3W = 60

W = 20 feet

L = 2W = 40 feet

Answer:

Let us check these out one at a time:

1. x + y is odd.  FALSE.  The sum of 2 odd numbers is even.

2. xy is odd.  TRUE.  The product of 2 odd numbers is odd.

3. x/y is odd.  TRUE.  The ratio of 2 odd numbers is odd, if the ratio is an integer.

4. x - y is odd.  FALSE.  The difference of 2 odd numbers is even.

Only statements 2 and 3 are TRUE, so that makes (C) the correct answer.

Answer:

5 %

Step-by-step explanation:

1000 g = 1 kg

50 kg = 0.05 kg

0.05 = 5%

Therefore, 50 g as a percentage of 1kg is 5%.

Answer:

x = 14

y = -7

z = -3

but this is none of the provided answer options !

Step-by-step explanation:

it's really easy by principle. it's just some work to do.

we try to find equations to express one variable in terms of the others.

but one thing there is : your teacher made a mistake.

the right solution is x = 14, y = -7, z = -3

your teacher made a typo at d.

but the right answer should be d.

just to give you an idea how this can be done (and also to prove that there is a mistake by the teacher):

we can directly try to transform one expression into one that describes x by y and z.

and then another to describe e.g. z by y. and then solve the third one just for y. and then we get the other 2 by these other expressions.

or we can e.g. add or subtract one equation to/from another. this is one of these cases, because we can find really simple expressions that way :

we do

5x + 6y + 7z = 7

- (3x + 4y + 3z = 5)

- (2x + 2y + 3z = 5)

---------------------------

0x + 0y + z = -3

=> z = -3

3x + 4y - 3×3 = 5

3x = -4y + 14

x = (-4y + 14)/3

2×(-4y + 14)/3 + 2y - 9 = 5

(-8y + 28)/3 + 2y = 14

-8y + 28 + 6y = 42

-2y = 14

y = -7

x = (-4×-7 + 14)/3 = (28+14)/3 = 42/3 = 14

9514 1404 393

Answer:

  (x, y') = (-13, 13)

Step-by-step explanation:

At the given value of x, f(x) = 2. Then 9f(x)-5 = 9(2) -5 = 13.

The point on the scaled, translated graph will be ...

  (x, y') = (-13, 13)

_____

The graph shows a function f(x) with a distinct feature (vertex) at (-13, 2). It also shows where that distinct feature moves to when the function is scaled and translated.

Answer:

x > 8

Step-by-step explanation:

You can start y multiplying both sides by 4 to cancel out the division by 4:

x/4 > 2

*4      *4

x > 8

Answer:

x > 8

Step-by-step explanation:

x/4 > 2

=> x > 2 × 4

=> x > 8

Answer:

C. 44.98

Step-by-step explanation:

Hi there!

We are given the right triangle ABC, m<B=12°, and CB =44

We want to find the length of AB

We can use trigonometry to do it

Let's find the ratio in reference to angle B, as that angle is given.

In reference to angle B the opposite angle is AC, the adjacent side is CB, and the hypotenuse is AB

Now let's recall the 3 most commonly used functions:

[tex]sine=\frac{opposite}{hypoptenuse}[/tex]

[tex]cosine=\frac{adjacent}{hypotenuse}[/tex]

[tex]tangent=\frac{opposite}{adjacent}[/tex]

Let's find the cosine of angle B, as it uses CB and AB, which are the given side and the side we need to find

In that case,

cos(12)=[tex]\frac{CB}{AB}[/tex]

cos(12)=[tex]\frac{44}{AB}[/tex]

Multiply both sides by AB

[tex]AB[/tex]*cos(12)=44

Divide both sides by cos(12)

AB=[tex]\frac{44}{cos(12)}[/tex]

Now plug [tex]\frac{44}{cos(12)}[/tex] into your calculator. Make sure your calculator is on degree mode

AB≈44.98

So the answer is C

Hope this helps!

Answer:

a. 9 students

b. 20 students

c. 4 students

Answer:

Step-by-step explanation:

400*e^(.09*3)

$523.97

answer is b

Answer: Option B

$523.97

Explanation:

= 400×e^(0.09×3)

= $523.97

Must click thanks and mark brainliest

Answer:

A

Step-by-step explanation:

I guess that is it may be