will rate you brainliest

Answer:

Step-by-step explanation:

[tex] \sf{ - 7y = - 91}[/tex]

Divide both sides of the equation by -7

⇒[tex] \sf{ \frac{ - 7y}{ - 7} = \frac{ - 91}{ - 7} }[/tex]

Calculate

⇒[tex] \sf{y = 13}[/tex]

Hope I helped!

Best regards!!

Answer:

[tex] \boxed{\sf y = 13} [/tex]

Step-by-step explanation:

Solve for y:

[tex] \sf \implies - 7y = - 91[/tex]

Divide both sides of -7y = -91 by -7:

[tex] \sf \implies \frac{ - 7y}{ - 7} = \frac{ - 91}{ - 7} [/tex]

[tex] \sf \frac{ - 7}{ - 7} = 1 : [/tex]

[tex] \sf \implies y = \frac{ - 91}{ - 7} [/tex]

[tex] \sf \implies y = \frac{ \cancel{ - 7} \times 13}{ \cancel{ - 7}} [/tex]

[tex] \sf \implies y = 13[/tex]

Complete Question

A research center claims that ​30% of adults in a certain country would travel into space on a commercial flight if they could afford it. In a random sample of 700 adults in that​ country, ​34% say that they would travel into space on a commercial flight if they could afford it. At ​, is there enough evidence to reject the research center's claim

Answer:

Yes there is  sufficient evidence to reject the research center's claim.

Step-by-step explanation:

From the question we are told that

     The population proportion is  p = 0.30

      The sample proportion is  [tex]\r p = 0.34[/tex]

       The  sample size is  n = 700

The null hypothesis is  [tex]H_o : p = 0.30[/tex]

 The  alternative hypothesis is  [tex]H_a : p \ne 0.30[/tex]

Here we are going to be making use of  level of significance  =  0.05 to carry out this test

Now we will obtain the critical value of  [tex]Z_{\alpha }[/tex] from the normal distribution table , the value is  [tex]Z_{\alpha } = 1.645[/tex]

 Generally the test statistics is mathematically represented as

            [tex]t = \frac{ \r p - p }{ \sqrt{ \frac{ p (1-p)}{n} } }[/tex]

substituting values

              [tex]t = \frac{ 0.34 - 0.30 }{ \sqrt{ \frac{ 0.30 (1-0.30 )}{ 700} } }[/tex]

              [tex]t = 2.31[/tex]

Looking at the values of t  and  [tex]Z_{\alpha }[/tex] we see that [tex]t > Z_{\alpha }[/tex] hence the null hypothesis is rejected

 Thus we can conclude that there is  sufficient evidence to reject the research center's claim.

Answer:

40 mL of 10% acid

80 mL of 25% acid

Step-by-step explanation:

x = volume of 10% acid solution

y = volume of 25% acid solution

Total volume is:

x + y = 120

Total amount of acid is:

0.10 x + 0.25 y = 0.20 (120)

Solve by substitution.

0.10 x + 0.25 (120 − x) = 0.20 (120)

0.10 x + 30 − 0.25 x = 24

0.15 x = 6

x = 40

y = 80

Complete Question

I = prt is an example of

• a variable

• an expression

• a constant

• a formula

Answer:

A formula

Step-by-step explanation:

I = prt is an example of a formula called Simple Interest.

Simple Interest can be defined as the formula that is used to calculate the interest that is accumulated on a particular amount of money which was saved in a financial institution or loaned out to a person at a given interest rate for a particular period of time.

The formula for Simple Interest is Expressed as:

I = PRT

Where :

I = Simple Interest

P = Principal = Amount saved, or loaned out

R = Interest rate that is given in percentage form

T = Time that has elapsed in Years.

Answer:

D. A Formula

Step-by-step explanation:

A formula is an equation that uses variables to state a rule.

Hope I was able to help you!

The statement is false. A sampling distribution is normal if either n > 30 or the population is normal.

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

Explanation:

If the underlying population is normally distributed, then so is the sample distribution (such as the distribution of sample means, aka xbar distribution).

Even if the population isn't normally distributed, the xbar distribution is approximately normal if n > 30 due to the central limit theorem. Some textbooks may use a higher value than 30, but after some threshold is met is when the xbar distribution is effectively "normal".

Choice A is close, but is missing the part about the population being normal. If we know the population is normal, then n > 30 doesn't have to be required.

Answer:

Perimeter of ABCD = 36 ft

Step-by-step explanation:

Given:

A (1,7)

B (7,7)

C (7,1)

D (1,1)

Find:

Perimeter of ABCD

Computation:

Distance between two point = √(x1-x2)² + (y1-y2)²

So,

AB = √(1-7)²+(7-7)²

AB = 6 ft

BC = √(7-7)²+(7-1)²

BC = 6 ft

CD = √(7-1)²+(1-1)²

CD = 6 ft

DA = √(1-1)²+(1-7)²

DA = 6 ft

Perimeter of ABCD = AB + BC + CD + DA

Perimeter of ABCD = 6 + 6 + 6 +6

Perimeter of ABCD = 36 ft

The perimeter of the plot is the sum of side length of the plot of land.

The perimeter of the plot is 24 feet.

Represent the vertices as follows:

[tex]W = (1,7)[/tex]

[tex]X = (7,7)[/tex]

[tex]Y = (7,1)[/tex]

[tex]Z = (1,1)[/tex]

First, we calculate the side length using the following distance formula:

[tex]d = \sqrt{(x_1 - x_2)^2 + (y_1 - y_2)^2}[/tex]

So, we have:

[tex]WX = \sqrt{(1- 7)^2 + (7- 7)^2} = \sqrt{36} = 6[/tex]

[tex]XY = \sqrt{(7- 7)^2 + (7- 1)^2} = \sqrt{36} = 6[/tex]

[tex]YZ = \sqrt{(7- 1)^2 + (1- 1)^2} = \sqrt{36} = 6[/tex]

[tex]ZW = \sqrt{(1- 1)^2 + (1- 7)^2} = \sqrt{36} = 6[/tex]

The perimeter (P) is then calculated as follows:

[tex]P = WX + XY + YZ + ZW[/tex]

So, we have:

[tex]P = 6 + 6 + 6 + 6[/tex]

[tex]P = 24[/tex]

Hence, the perimeter of the plot of land is 24 feet.

Read more about perimeters at:

https://brainly.com/question/394193

Answer:

B = 34.2°

C = 105.8°

c = 12.0 units

Step-by-step Explanation:

Given:

A = 40°

a = 8

b = 7

Required:

Find B, C, and c.

SOLUTION:

Using the Law of Sines, find <B:

[tex] \frac{sin(A)}{a} = \frac{sin(B)}{b} [/tex]

[tex] \frac{sin(40)}{8} = \frac{sin(B)}{7} [/tex]

Multiply both sides by 7

[tex] \frac{sin(40)}{8}*7 = \frac{sin(B)}{7}*7 [/tex]

[tex] \frac{sin(40)*7}{8} = sin(B) [/tex]

[tex] 0.5624 = sin(B) [/tex]

[tex] B = sin^{-1}(0.5624) [/tex]

[tex] B = 34.2 [/tex] (to nearest tenth).

Find <C:

C = 180 - (34.2+40°) (sum of angles in a triangle)

C = 180 - 74.2 = 105.8°

Using the Law of Sines, find c.

[tex] \frac{c}{sin(C)} = \frac{b}{sin(B)} [/tex]

[tex]\frac{c}{sin(105.8)} = \frac{7}{sin(34.2)}[/tex]

Multiply both sides by sin(105.8)

[tex]\frac{c}{sin(105.8)}*sin(105.8) = \frac{7}{sin(34.2)}*sin(105.8)[/tex]

[tex] c = \frac{7*sin(105.8)}{sin(34.2)} [/tex]

[tex] c = 12.0 [/tex]

Answer:

150+233-64=319

Jim is 319 ft above sea level.

Step-by-step explanation:

Answer: 7

Step-by-step explanation:

Answer :

It Is 7 On Khan Academy

◊ YusuCr ◊

:)

Answer:

Both angle measures and segment lengths.

Step-by-step explanation:

An angle is a shape formed by two rays that meets at a point. The angle is measured by degrees. The angle is formed by the sides of an angle which shares the common endpoint called the vertex. The line is horizontal stretch with a vertical line PQ. It will measure the angle and segments lengths.

Answer:

neither angle measures nor segment lines

Answer:

These are the first 100 digits of pi: 3.14159 26535 89793 23846 26433 83279 50288 41971 69399 37510 58209 74944 59230 78164 06286 20899 86280 34825 34211 7067

Step-by-step explanation:

Pi goes on continuously forever, so this is a reduced version, by including the first 100 digits.

Answer:

a. the largest number of observations.

Step-by-step explanation:

The mode is the variable in a data that has the highest frequency. Which implies that it occurs more than other variables.

When plotting a histogram, the modal class is one that has the greatest number of observations. Showing that the variables comprised in the class has more occurrence than others. Therefore, the required answer to the question is option a.

Answer:

Step-by-step explanation:

Given that:

A simple random sample n = 28

sample standard deviation S = 12.65

standard deviation [tex]\sigma[/tex] = 11.53

Level of significance ∝ = 0.05

The objective is to test the claim that the number of pieces in a set has a standard deviation different from 11.53.

The null hypothesis and the alternative hypothesis can be computed as follows:

Null hypothesis:

[tex]H_0: \sigma^2 = \sigma_0^2[/tex]

Alternative hypothesis:

[tex]H_1: \sigma^2 \neq \sigma_0^2[/tex]

The test statistics can be determined by using the following formula in order to test if the claim is statistically significant or not.

[tex]X_0^2 = \dfrac{(n-1)S^2}{\sigma_0^2}[/tex]

[tex]X_0^2 = \dfrac{(28-1)(12.65)^2}{(11.53)^2}[/tex]

[tex]X_0^2 = \dfrac{(27)(160.0225)}{132.9409}[/tex]

[tex]X_0^2 = \dfrac{4320.6075}{132.9409}[/tex]

[tex]X_0^2 = 32.5002125[/tex]

[tex]X^2_{1- \alpha/2 , df} = X^2_{1- 0.05/2 , n-1}[/tex]

[tex]X^2_{1- \alpha/2 , df} = X^2_{1- 0.025 , 28-1}[/tex]

From the chi-square probabilities table at 0.975 and degree of freedom 27;

[tex]X^2_{0.975 , 27}[/tex] = 14.573

[tex]X^2_{\alpha/2 , df} = X^2_{ 0.05/2 , n-1}[/tex]

[tex]X^2_{\alpha/2 , df} = X^2_{0.025 , 28-1}[/tex]

From the chi-square probabilities table at 0.975 and degree of freedom 27;

[tex]X^2_{0.025 , 27}=[/tex] 43.195

Decision Rule: To reject the null hypothesis if [tex]X^2_0 \ > \ X^2_{\alpha/2 , df} \ \ \ or \ \ \ X^2_0 \ < \ X^2_{1- \alpha/2 , df}[/tex] ; otherwise , do not reject the null hypothesis:

The rejection region is [tex]X^2_0 \ > 43.195 \ \ \ or \ \ \ X^2_0 \ < \ 14.573[/tex]

Conclusion:

We fail to reject the null hypothesis since  test statistic value 32.5002125  lies  between 14.573 and 43.195.

Answer:

A

   The  correct option is B

B

   [tex]t = 0.6093[/tex]

C

 [tex]p-value = 0.27116[/tex]

D

The  correct option is  D

Step-by-step explanation:

From the question we are told that

    The  sample size is  [tex]n = 232[/tex]

    The  number that developed  nausea  is X =  50

    The population proportion is  p  =  0.20  

The  null hypothesis is   [tex]H_o : p = 0.20[/tex]

The  alternative hypothesis is  [tex]H_a : p > 0.20[/tex]

Generally the sample proportion is mathematically represented as

     [tex]\r p = \frac{50}{232}[/tex]

     [tex]\r p = 0.216[/tex]

Generally the test statistics is mathematically represented as

 =>           [tex]t = \frac{\r p - p }{ \sqrt{ \frac{p(1- p )}{n} } }[/tex]

=>           [tex]t = \frac{ 0.216 - 0.20 }{ \sqrt{ \frac{ 0.20 (1- 0.20 )}{ 232} } }[/tex]

=>        [tex]t = 0.6093[/tex]

The  p-value obtained from the z-table is

       [tex]p-value = P(Z > 0.6093) = 0.27116[/tex]

  Given that the  [tex]p-value > \alpha[/tex]  then we fail to reject the null hypothesis

Answer: the distance is  3.49 units

Step-by-step explanation:

There are some ways to find the exact distance, i will calculate the distance in rectangular coordinates.

When we have a point (R, θ) in polar coordinates, we can transform it into rectangular coordinates as:

x = R*cos(θ)

y = R*sin(θ)

Then we have:

(7,217pi/180 )

R = 7

θ = (217/180)*pi

x = 7*cos( (217/180)*pi) = -5.59

y = 7*sin( (217/180)*pi) = -4.21

So this point is (-5.59, -4.21) in rectangular coordinates.

And the other point is  (5,-23pi/36 )

R = 5

θ = -(23/36)*pi

x = 5*cos(  -(23/36)*pi ) = -2.11

y = 5*sin(  -(23/36)*pi ) = -4.53

So this point is (-2.11, - 4.53)

Then the point distance between those points is:

D = I (-2.11, -4.53) - (-5.59, -4.21) I

D = I (-2.11 + 5.59, -4.53 + 4.21) I

D = I (3.48, -0.32) I = √( (3.48)^2 + (-0.32)^2) =  3.49

Answer:

6/50

Step-by-step explanation:

There are 50 tiles

6 purple

18 pink

26 orange

P( purple) = purple/ total

                = 6/50

Step-by-step explanation:

Find the z-score.

z = (x − μ) / σ

z = (109.8 − 106.9) / 14.5

z = 0.2

Use a chart or calculator to find the probability.

P(Z < 0.2) = 0.5793

Find the mean and standard deviation of the sampling distribution.

μ = 106.9

σ = 14.5 / √20 = 3.242

Find the z-score.

z = (x − μ) / σ

z = (109.8 − 106.9) / 3.242

z = 0.894

Use a calculator to find the probability.

P(Z < 0.894) = 0.8145

Answer:

The mean commute time in the U.S. is less than half an hour.

Step-by-step explanation:

In this case we need to test whether the mean commute time in the U.S. is less than half an hour.

The information provided is:

 [tex]n=45\\\bar x=25.5\\s=19.1\\\alpha =0.05[/tex]

(a)

The hypothesis for the test can be defined as follows:

H₀: The mean commute time in the U.S. is not less than half an hour, i.e. μ ≥ 30.

Hₐ: The mean commute time in the U.S. is less than half an hour, i.e. μ < 30.

(b)

As the population standard deviation is not known we will use a t-test for single mean.

Compute the test statistic value as follows:

 [tex]t=\frac{\bar x-\mu}{s/\sqrt{n}}=\frac{25.2-30}{19.1/\sqrt{45}}=-1.58[/tex]

Thus, the test statistic value is -1.58.

(c)

Compute the p-value of the test as follows:

[tex]p-value=P(t_{(n-1)}<-1.58)=P(t_{(45-1)}<-1.58)=0.061[/tex]  

*Use a t-table.

The p-value of the test is 0.061.

Decision rule:

If the p-value of the test is less than the significance level then the null hypothesis will be rejected and vice-versa.

p-value = 0.061> α = 0.05

The null hypothesis will not be rejected at 5% level of significance.

Thus, concluding that the mean commute time in the U.S. is less than half an hour.

Answer:

continuous

Step-by-step explanation:

A quantity like temperature is a continuous random variable. A continuous random variable is different from a discrete random variable because it can take on many values infinitely.

From the question, measuring the Temperature in degrees can take on many different values because there are an uncountable number of possible temperatures that could be taken.

Answer:

work is shown and pictured

Answer:

Hi, there!!!

The answer would be 2(2x-1)/x(x-4).

See explanation in picture.

Hope it helps...

Complete Questions:

Create an equation with a solution closest to 0 using digits 1 to 9

_x + _ = _x + _

Answer:

See Explanation

Step-by-step explanation:

Given

_x + _ = _x + _

Required

Fill in the gap using 1 to 9 to give a result close to 0

First, you have to determine what kind of numbers that are close to 0;

In this case, I'll work with -0.4 to 0.4 because the number in this range approximate to 0;

Next, is to fill in the gaps using trial by error method

5x + 2 = 2x + 3

Checking the above expression

Collect Like Terms

[tex]5x - 2x = 3 - 2[/tex]

[tex]3x = 1[/tex]

Divide equation by 2

[tex]x = 0.33[/tex] (Approximated)

Another trial is

6x + 8 = 2x + 7

Checking the above expression

Collect Like Terms

[tex]6x - 2x = 7 - 8[/tex]

[tex]4x = -1[/tex]

Divide equation by 4

[tex]x = -0.25[/tex] (Approximated)

I'll stop here but note that, there are more expressions that can fill in the gaps

Answer:

0.30924

Approximately ≈ 0.3092

Step-by-step explanation:

To solve for this question, we use the formula:

z = (x - μ)/σ

where x is the raw score

μ is the sample mean

σ is the sample standard deviation.

From the question,

x is the raw score = 260

μ is the sample mean = population standard deviation = 258

σ is the sample standard deviation

= σ/√N

N = 76 samples

σ = Population standard deviation

= 35/√76

= 4.0146919966

Hence,

z = (x - μ)/σ

= 260 - 258/ 4.0146919966

= 0.4981702212

Approximately = 0.498

We find the Probability using z score table for normal distribution

P(x = z) = P( x = 260)

= P( z = 0.498)

= 0.69076

The probability that a random customer will have more than $260 in his or her wallet is calculated as:

P(x>Z) = 1 - P( z = 0.498)

P(x>Z) = 1 - 0.69076

P(x>Z) = 0.30924

Approximately ≈ 0.3092

Answer:

3

Step-by-step explanation:

z - 2x

--------

y

Let x = 3  y = -4 and z  =-6

-6 - 2(3)

--------

-4

-6 -6

---------

-4

-12

-----

-4

3

Answer:

3

Step-by-step explanation:

To solve this, we need to plug in each of the numbers to the equation.

x = 3, y = - 4, z = - 6

[tex]\frac{z-2x}{y} = \frac{-6-2(3)}{-4}[/tex]

Let's solve the parenthesis first. - 2 * 3 = - 6.

[tex]\frac{-6-6}{-4}[/tex]

We then subtract -6 - 6.

[tex]\frac{-12}{-4}[/tex]

Then, we divide (cancel out the negatives).

[tex]-12 / -4 =3[/tex]

Our final answer is 3. Hope this helps!

Answer:

B y = -1/2x + 7/2

Step-by-step explanation:

We know that it has a negative slope since the points go from the top left to the bottom right

We can eliminate A and D

The y intercept is where it crosses the y axis

It should cross somewhere between 2 and 4

C  has a y intercept of 9 which is too big

Lets verify with a point

x = -4

y = -4(-4)+9 = 16+9 = 25  (-4,25)  not even close to being near the points on the graph

checking B

y = -1/2 (-4) +7/2

  = 2 + 7/2 = 11/2 = 5.5  it seems  reasonable

Answer:

[tex]\Large \boxed{y=-\frac{1}{2} x+\frac{7}{2} }[/tex]

Step-by-step explanation:

Using a graph,

we can see that the line y = -1/2x + 7/2 best fits for the data.

Step-by-step explanation:

Here,

[tex]5y = 4x - 12 - 10[/tex]

[tex]y = \frac{4}{5} x - \frac{22}{5} [/tex]

slope is 4÷5

Answer:

Step-by-step explanation:

Equation of a line is y = mx + c

where

m is the slope

c is the y intercept

5(y+2)=4(x-3)

To find the slope first expand the terms in the equation

That's

5y + 10 = 4x - 12

Write the equation in the form y = mx+ c

That's

5y = 4x - 12 - 10

5y = 4x - 22

Divide both sides by 5 to make y stand alone

y = 4/5x - 22/5

Comparing with the general equation above the slope of the line is

Hope this helps you

Answer:

[tex]\displaystyle \oint_C {3y \, dx + 2x \, dy} = \boxed{\bold{2}}[/tex]

General Formulas and Concepts:
Calculus

Differentiation

Derivative Property [Multiplied Constant]:
[tex]\displaystyle (cu)' = cu'[/tex]
Derivative Rule [Basic Power Rule]:

Integration

Integration Rule [Fundamental Theorem of Calculus 1]:
[tex]\displaystyle \int\limits^b_a {f(x)} \, dx = F(b) - F(a)[/tex]

Integration Property [Multiplied Constant]:
[tex]\displaystyle \int {cf(x)} \, dx = c \int {f(x)} \, dx[/tex]

Multivariable Calculus

Partial Derivatives

Vector Calculus

Circulation Density:
[tex]\displaystyle F = M \hat{\i} + N \hat{\j} \rightarrow \text{curl} \ \bold{F} \cdot \bold{k} = \frac{\partial N}{\partial x} - \frac{\partial M}{\partial y}[/tex]

Green's Theorem [Circulation Curl/Tangential Form]:
[tex]\displaystyle \oint_C {F \cdot T} \, ds = \oint_C {M \, dx + N \, dy} = \iint_R {\bigg( \frac{\partial N}{\partial x} - \frac{\partial M}{\partial y} \bigg)} \, dx \, dy[/tex]

Step-by-step explanation:

Step 1: Define

Identify given.

[tex]\displaystyle \oint_C {3y \, dx + 2x \, dy}[/tex]

[tex]\displaystyle \text{Region:} \ \left \{ {{0 \leq x \leq \pi} \atop {0 \leq y \leq \sin x}} \right.[/tex]

Step 2: Integrate Pt. 1

Step 3: Integrate Pt. 2

We can evaluate the Green's Theorem double integral we found using basic integration techniques listed above:
[tex]\displaystyle \begin{aligned}\oint_C {3y \, dx + 2x \, dy} & = - \int\limits^{\pi}_0 \int\limits^{\sin x}_0 {} \, dy \, dx \\& = - \int\limits^{\pi}_0 {y \bigg| \limits^{y = \sin x}_{y = 0}} \, dx \\& = - \int\limits^{\pi}_0 {\sin x} \, dx \\& = \cos x \bigg| \limits^{x = \pi}_{x = 0} \\& = \boxed{\bold{2}}\end{aligned}[/tex]

∴ we have evaluated the line integral using Green's Theorem.

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Learn more about multivariable calculus: https://brainly.com/question/14502499

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Topic: Multivariable Calculus

Unit: Green's Theorem and Surfaces

Answer:

Step-by-step explanation:

vertical stretching / shrinking has the following transformation.

f(x) -> a * f(x)

when a >  1, it is stretching

when 0< a < 1, it is shrinking.

when  -1 < a < 0, it is shringking + reflection about the x-axis

when a < -1, it is stretching + reflection about the x axis.

Here it is simple shrinking, so 0 < a < 1.

I expect the answer choice to show (1/3) f(x).

However, if the question plays with the words

"shrink by a factor of 1/3" to actually mean a "stretching by a factor of three", then B is the answer (stretch by a factor of three).

Answer:

I only know two right answers.

A: The center of dilation is point C.

C: It is an enlargement.

E: The scale factor is 2/5.

Step-by-step explanation:

These two answers are correct because When you look in the center you see a C.

You tell if it is a reduction because the pre image is small but the image is big.

The center of dilation is point C.

It is an enlargement.

The scale factor is 2/5

The correct options are D, F, H.

Resizing an item uses a transformation called dilation. Dilation is used to enlarge or shorten the structures. The result of this transformation is an image with the same shape as the original. However, there is a variation in the shape's size. The initial form should be stretched or contracted during a dilatation.

Given:

The transformation of the figure is dilation.

The figure is given in the attached image.

From the diagram:

The center of dilation is point C.

It is an enlargement.

The scale factor is 2/5

Therefore, all the correct statements are given above.

To learn more about the dilation in geometry;

https://brainly.com/question/10713409

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Answer: The multiplicative inverse of – 1 in the set {-1,1} is -1.

Step-by-step explanation:

In algebra, the multiplicative inverse of a number(x) is a number (say y) such that

[tex]x\times y=1[/tex]  [product of a number and its inverse =1]

if x= -1, then

[tex]-1\times y=1\Rightarrow\ y=-1[/tex]

That means , the multiplicative inverse of -1 is -1 itself.

Hence, the multiplicative inverse of – 1 in the set {-1,1} is -1.

Answer:

3 miles

Step-by-step explanation:

5 + m=8

Subtract 5 from each side

5-5 + m=8-5

m = 3

She needs to swim 3 more miles

Answer:

Yelena needs to swim 3 more miles

Step-by-step explanation:

You need to solve for the variable "m", which represents the miles. Based on the information, Yelena swam 5 miles and she needs to swim 8. Solve:

[tex]5+m=8[/tex]

To find the value of m, you need to isolate it on one side of the equation. To do this, you need to get the 8 and 5 on the same side of the equal operation. For this, you need to use reverse operations. This undoes the value from one side and does the same on the other, keeping the equation balanced. Since we have a "positive 5", we take the opposite, which would be a "negative 5". So subtract 5 from both sides of the equation:

[tex]5-5+m=8-5[/tex]

Simplify. The 5's cancel each other out, leaving 0. 8-5 is 3:

[tex]m=3[/tex]

The total miles left that Yelena needs to swim is 3 miles.

:Done