Please Show Work So I Can Grasp The Concept Of This Equation​

Answer:

There is a 95% chance that the population mean is between 73.9 and 76.1 beats per minute.

Step-by-step explanation:

i have the test

There is a 95% chance that the population mean is between 73.9 and 76.1 beats per minute.

Since

The average heart rate was 75 beats per minute.

The standard deviation is 8 beats per minute

And, there is the study of 205 adults

Now the following formula is to be used

Since

[tex]x \pm z \frac{\sigma}{\sqrt{n} }[/tex]

Here

z = 1.96 at 95% confidence interval

So,

[tex]= 75 \pm 1.96 \frac{8}{\sqrt{205} } \\\\= 75 - 1.96 \frac{8}{\sqrt{205} } , 75 + 1.96 \frac{8}{\sqrt{205} }[/tex]

= 73.9 ,76.1

Hence, the above statement should be true.

Learn more about standard deviation here: https://brainly.com/question/20529928

Answer:

77.64% probability that there will be 0 or 1 defects in a sample of 6.

Step-by-step explanation:

For each item, there are only two possible outcomes. Either it is defective, or it is not. The probability of an item being defective is independent of other items. So we use the binomial probability distribution to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.

[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]

And p is the probability of X happening.

The true proportion of defects is 0.15

This means that [tex]p = 0.15[/tex]

Sample of 6:

This means that [tex]n = 6[/tex]

What is the probability that there will be 0 or 1 defects in a sample of 6?

[tex]P(X \leq 1) = P(X = 0) + P(X = 1)[/tex]

In which

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]P(X = 0) = C_{6,0}.(0.15)^{0}.(0.85)^{6} = 0.3771[/tex]

[tex]P(X = 1) = C_{6,1}.(0.15)^{1}.(0.85)^{5} = 0.3993[/tex]

[tex]P(X \leq 1) = P(X = 0) + P(X = 1) = 0.3771 + 0.3993 = 0.7764[/tex]

77.64% probability that there will be 0 or 1 defects in a sample of 6.

Answer:

0.11

Step-by-step explanation:

Let the random variable score, X = 26; mean, ∪ = 19.6; standard deviation, α = 5.2

By comparing P(0≤ Z ≤ 26)

P(Z ≤ X - ∪/α) = P(Z ≤ 26 - 19.6/5.2)

= P(Z ≤ 1.231)

Using Table: P(0 ≤ Z ≤ 1) = 0.39

P(Z > 1) = (0.5 - 0.39) = 0.11

∴ P(Z > 26) = 0.11

Answer:

97.5 minutes or 1.63 hours

Step-by-step explanation:

1. Find the amount of time it takes to travel 1 mile

[tex]\frac{60}{230}[/tex] = 0.26 minutes

2. Multiply the distance by the time it takes to travel 1 mile

375 · 0.26 = 97.5 minutes

To convert to hours, divide by 60 because there are 60 minutes in 1 hour.

97.5 ÷ 60 = 1.63 hours

Answer:

The probability plot of this distribution shows that it is approximately normally distributed..

Check explanation for the reasons.

Step-by-step explanation:

The complete question is attached to this solution provided.

From the cumulative probability plot for this question, we can see that the plot is almost linear with no points outside the band (the fat pencil test).

The cumulative probability plot for a normal distribution isn't normally linear. It's usually fairly S shaped. But, when the probability plot satisfies the fat pencil test, we can conclude that the distribution is approximately linear. This is the first proof that this distribution is approximately normal.

Also, the p-value for the plot was obtained to be 0.541.

For this question, we are trying to check the notmality of the distribution, hence, the null hypothesis would be that the distribution is normal and the alternative hypothesis would be that the distribution isn't normal.

The interpretation of p-valies is that

When the p-value is greater than the significance level, we fail to reject the null hypothesis (normal hypothesis) and but if the p-value is less than the significance level, we reject the null hypothesis (normal hypothesis).

For this distribution,

p-value = 0.541

Significance level = 0.05 (Evident from the plot)

Hence,

p-value > significance level

So, we fail to reject the null or normality hypothesis. Hence, we can conclude that this distribution is approximately normal.

Hope this Helps!!!

Answer:

Step-by-step explanation:

Surface Area of the rectangular box = 2(LW+LH+WH)

L is the length of the box

W is the width of the box

H is the height of the box

let dL, dW and dH be the possible error in the dimensions L, W and H respectively.

Since there is a possible error of 0.2cm in each dimension, then dL = dW = dH = 0.2cm

The surface Area of the rectangular box using the differentials is expressed as shown;

S = 2{(LdW+WdL)+(LdH+HdL)+(WdH+HdW)]

Also given L = 96cm W = 58cm and H = 48cm, on substituting this given values and the differential error, we will have;

S = 2{(96*0.2+58*0.2) + (96*0.2+48*0.2)+(58*0.2+48*0.2)}

S = 2{19.2+11.6+19.2+9.6+11.6+9.6}

S = 2(80.8)

S = 161.6 cm²

Hence, the surface area of the box is 161.6 cm²

Answer: 2

Step-by-step explanation:

As given, out of 30 students, 15 play guitar and 13 play piano, thats 28.

Among these, 9 play both the guitar and the piano.

That means, only 2 remaining students play neither instrument. (30-15-13)

Answer:

The area of the remaining board is (x² - 289) sq. ft.

Step-by-step explanation:

Let the sides of the bigger square board be, x feet.

It is provided that a smaller square of side length 17 feet is cut out of the bigger square board.

The area of a square is:

[tex]Area=(side)^{2}[/tex]

Compute the area of the bigger square board as follows:

[tex]A_{b}=(side_{b})^{2}=x^{2}[/tex]

Compute the area of the smaller square board as follows:

[tex]A_{s}=(side_{s})^{2}=(17)^{2}=289[/tex]

Compute the area of the remaining board in square feet as follows:

[tex]\text{Remaining Area}=A_{b}-A_{s}[/tex]

                          [tex]=[x^{2}-289]\ \text{square ft.}[/tex]

Thus, the area of the remaining board is (x² - 289) sq. ft.

Answer:

It is better for the warriors to use man-to-man defense.

Step-by-step explanation:

The complete question is: The Westwood Warriors basketball team wants to score more points. To get better at scoring points the  team is trying to improve its offensive strategies. Some opponents primarily use a zone defense, while  others primarily use a man-to-man defense. When the Warriors play against teams that use a zone defense they score an average of 67 points per game with a standard deviation of 8 points per game. When they play against teams that use a  man-to-man defense they score an average of 62 points per game with a standard deviation of 5 points per game.

Since the Warriors started using their improved offensive strategies they have played two  games with the following results.

Against the McNeil Mavericks

Maverick defense: zone

Warrior points: 77

Against the Round Rock Dragons

Dragon defense: man-to-man

Warrior points: 71

What is the Z-score of these values?

We are given that when the Warriors play against teams that use a zone defense they score an average of 67 points per game with a standard deviation of 8 points per game. When they play against teams that use a  man-to-man defense they score an average of 62 points per game with a standard deviation of 5 points per game.

We have to find the z-scores.

Let X = points score by warriors when they use zone defense

The z-score probability distribution for the normal distribution is given by;

                            Z  =  [tex]\frac{X-\mu}{\sigma}[/tex]  ~ N(0,1)

where, [tex]\mu[/tex] = mean score = 67 points

            [tex]\sigma[/tex] = standard deviation = 8 points

It is stated that the Warriors scored 77 points when they used zone defense, so;

   z-score for 77 =  [tex]\frac{X-\mu}{\sigma}[/tex]

                            =  [tex]\frac{77-67}{8}[/tex]  = 1.25

Let X = points score by warriors when they use man-to-man defense

The z-score probability distribution for the normal distribution is given by;

                            Z  =  [tex]\frac{X-\mu}{\sigma}[/tex]  ~ N(0,1)

where, [tex]\mu[/tex] = mean score = 62 points

            [tex]\sigma[/tex] = standard deviation = 5 points

It is stated that the Warriors scored 71 points when they used man-to-man defense, so;

   z-score for 71 =  [tex]\frac{X-\mu}{\sigma}[/tex]

                            =  [tex]\frac{71-62}{5}[/tex]  = 1.8

So, it is better for the warriors to use man-to-man defense.

Step-by-step explanation:

it can be simply done by using remainder theorem.

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▹ Answer

0.25 = 1/4 because 25/100 = 1/4

▹ Step-by-Step Explanation

0.25 to a fraction → 25/100

25/100 = 1/4

Therefore, this statement is true. (0.25 = 1/4 because 25/100 = 1/4)

Hope this helps!

- CloutAnswers ❁

Brainliest is greatly appreciated!

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Answer:

  C)  42

Step-by-step explanation:

The parallel lines divide the transversals proportionally.

  x/35 = 30/25

  x = 35(6/5) . . . . multiply by 35, reduce the fraction

  x = 42

Answer:

y=6x+31

Step-by-step explanation:

Since we are given a point and a slope, we can use the slope-intercept formula.

[tex]y-y_{1} =m(x-x_{1})[/tex]

where (x1,y1) is a point on the line and m is the slope.

The point given is (-6,-5) and the slope is 6.

x1= -6

y1= -5

m=6

[tex]y--5=6(x--6)[/tex]

A negative number subtracted from another number, or two negative signs, becomes a positive.

[tex]y+5=6(x+6)[/tex]

We want to find the equation of the line, which is y=mx+b (m is the slope and b is the y-intercept). Therefore, we must get y by itself on one side of the equation.

First, distribute the 6. Multiply each term inside the parentheses by 6.

[tex]y+5=(6*x)+(6*6)[/tex]

[tex]y+5=6x+36[/tex]

Subtract 5 from both sides, because it is being added on to y.

[tex]y+5-5=6x+36-5[/tex]

[tex]y=6x+36-5[/tex]

[tex]y=6x+31[/tex]

The equation of the line is y=6x+31

Answer:

Polygon is pentagon

Step-by-step explanation:

In a regular polygon each angle is equal.

In a regular polygon Each angle of polygon is given by (2n-4)90/n

where n is the number of sides of the polygon

given

An interior angle of a regular polygon has a measure of 108°.

(2n-4)90/n = 108

=> 180n - 360 = 108n

=> 180n-108n= 360

=> 72n = 360

=> n = 360/72 = 5

Thus, polygon has 5 sides

and we know that regular polygon which has 5 sides is called pentagon.

Thus, Polygon is pentagon

Answer:

1/256

Step-by-step explanation:

The table shows a chain of fractions for f(x), x1 is 1/4, x2 is 1/16 and x3 is 1/64. All you need to do is multiply the denominator by 4 and put 1 over it. 64*4 = 256, adding the 1 as the numerator gives us the answer of 1/256 as x4.

Answer:

The solution to the given Initial - Value - Problem is [tex]y(t) = \frac{-1}{9} + \frac{1}{3}t + \frac{1}{9}e^{-3t} - [\frac{-1}{9} + \frac{1}{3}t - \frac{2}{9}e^{-3(t-1)}]u(t-1)[/tex]

Step-by-step explanation:

y' + 3y = f(t).................(1)

f(t) = t      when 0 ≤ t < 1

f(t) = 0     when t ≥ 1

Step 1: Take the Laplace transform of the LHS of equation (1)

That is L(y' + 3y) = sY(s) + 3Y(s) = Y(s)[s + 3]..............(*)

Step 2: Get an expression for f(t)

For f(t) = t      when 0 ≤ t < 1

f₁(t) = t (1 - u(t - 1)) ( there is a time shift of the unit step)

For f(t) = 0     when t ≥ 1

f₂(t) = 0(u(t-1))

f(t) = f₁(t) + f₂(t)

f(t) = t - t u(t-1)................(2)

Step 3: Taking the Laplace transform of equation (2)

[tex]F(s) = \frac{1}{s^2} - e^{-s} ( \frac{1}{s^2} + \frac{1}{s})[/tex]...............(**)

Step 4: Equating * and **

[tex]Y(s) [s + 3]=\frac{1}{s^2} - e^{-s} ( \frac{1}{s^2} + \frac{1}{s}) \\Y(s) = \frac{1}{s^2(s+3)} - e^{-s} ( \frac{1}{s^2(s+3)} + \frac{1}{s(s+3)})[/tex].......................(3)

Since y(t) is the solution we are looking for we need to find the Inverse Laplace Transform of equation (3) by first breaking every  fraction into partial fraction:

[tex]\frac{1}{s^2 (s+3)} = \frac{-1}{9s} + \frac{1}{3s^2} + \frac{1}{9(s+3)}[/tex]

[tex]\frac{1}{s (s+3)} = \frac{1}{3s} + \frac{1}{3(s+3)}[/tex]

We can rewrite equation (3) by representing the fractions by their partial fractions.

[tex]Y(s) = \frac{-1}{9s} + \frac{1}{3s^2} + \frac{1}{9(s+3)} - e^{-s} [\frac{-1}{9s} + \frac{1}{3s^2} + \frac{1}{9(s+3)} + \frac{1}{3s} + \frac{1}{3(s+3)}]\\Y(s) = \frac{-1}{9s} + \frac{1}{3s^2} + \frac{1}{9(s+3)} - e^{-s}[\frac{2}{9s} + \frac{1}{3s^2} - \frac{2}{9(s+3)}][/tex]................(4)

step 5: Take the inverse Laplace transform of equation (4)

[tex]y(t) = \frac{-1}{9} + \frac{1}{3}t + \frac{1}{9}e^{-3t} - u(t-1)[\frac{2}{9} + \frac{1}{3}(t-1) - \frac{2}{9}e^{-3(t-1)}][/tex]

Simplifying the above equation:

[tex]y(t) = \frac{-1}{9} + \frac{1}{3}t + \frac{1}{9}e^{-3t} - [\frac{-1}{9} + \frac{1}{3}t - \frac{2}{9}e^{-3(t-1)}]u(t-1)[/tex]

The Laplace transform is use to solve the differential equation problem.

The solution for the given initial-value problem is,

[tex]y(t)=\dfrac{-1}{9}+\dfrac{-1}{3}t+\dfrac{1}{9}e^-3t-\left[\dfrac{-1}{9}+\dfrac{-1}{3}t+\dfrac{2}{9}e^{-3(t-1)}\right]u(t-1)[/tex]

Given:

The given initial value problem is [tex]y' + 3y = f(t)[/tex].

Consider the left hand side of the given equation.

[tex]y'+3y[/tex]

Take the Laplace transform.

[tex]L(y' + 3y) = sY(s) + 3Y(s) \\L(y' + 3y) = Y(s)[s + 3][/tex]

Consider the right hand side and get the expression for [tex]f(t)[/tex].

[tex]f(t) = t[/tex]  when 0 ≤ t < 1

From time shift of the unit step

[tex]f_1(t) = t (1 - u(t - 1))[/tex]

For f(t) = 0     when t ≥ 1

Now,

[tex]f_2(t) = 0(u(t-1))f(t) = f_1(t) + f_2(t)f(t) = t - t u(t-1)[/tex]

Take the Laplace for above expression.

[tex]F(s)=\dfrac{1}{s^2}-e^{-s}\left(\dfrac{1}{s^2}+\dfrac{1}{s}\right)[/tex]

Now, the equate the above two equation.

[tex]Y(s)\left[s+3\right ]=\dfrac{1}{s^2}-e^{-s}\left(\dfrac{1}{s^2}+\dfrac{1}{s}\right)\\Y(s)=\dfrac {1}{(s^2(s+3))}-e^{-s}\left(\dfrac{1}{(s^2(s+3))}+\dfrac{1}{s(s+3)\right)}[/tex]

Find the inverse Laplace for the above equation.

[tex]\dfrac{1}{(s^2(s+3))}=\dfrac{-1}{9s}+\dfrac{1}{3s^2}+\dfrac{1}{9(s+3)}\\\dfrac{1}{(s(s+3))}=\dfrac{1}{3s}+\dfrac{1}{3(s+3)}[/tex]

Calculate the partial fraction of above equation.

[tex]Y(s)=\dfrac{-1}{9s}+\dfrac{1}{3s^2}+\dfrac{1}{9(s+3)}-e^{-s}\left[\dfrac{-1}{9s}+\dfrac{1}{3s^2}+\dfrac{1}{9(s+3)}+\dfrac{1}{3s}+\dfrac{1}{3(s+3)}\right]\\Y(s)=\dfrac{2}{9s}+\dfrac{1}{3s^2}+\dfrac{1}{9(s+3)}-e^{-s}\left[\dfrac{2}{9s}+\dfrac{1}{3s^2}-\dfrac{2}{9(s+3)}\right][/tex]

Take the inverse Laplace of the above equation.

[tex]y(t)=\dfrac{-1}{9}+\dfrac{-1}{3}t+\dfrac{1}{9}e^-3t-\left[\dfrac{-1}{9}+\dfrac{-1}{3}t+\dfrac{2}{9}e^{-3(t-1)}\right]u(t-1)[/tex]

Thus, the solution for the given initial-value problem is,

[tex]y(t)=\dfrac{-1}{9}+\dfrac{-1}{3}t+\dfrac{1}{9}e^-3t-\left[\dfrac{-1}{9}+\dfrac{-1}{3}t+\dfrac{2}{9}e^{-3(t-1)}\right]u(t-1)[/tex]

Learn more about what Laplace transformation is here:

https://brainly.com/question/14487937

Answer:

d. The mean is 43.6°F, and the median is 43.5°F.

Step-by-step explanation:

Hello!

The data corresponds to the low temperatures in Phoenix recorded for April to November.

April: 32ºF

May: 40ºF

June: 50ºF

July: 61ºF

August: 60ºF

September: 47ºF

October: 34ºF

November: 25ºF

Sample size: n= 8 months

The mean or average temperature of the low temperatures in Phoenix can be calculated as:

[tex]\frac{}{X}[/tex]= ∑X/n= (32+40+50+61+60+47+34+25)/8= 43.625ºF (≅ 43.6ºF)

The Median (Me) is the value that separates the data set in two halves, first you have to calculate its position:

PosMe= (n+1)/2= (8+1)/2= 4.5

The value that separates the sample in halves is between the 4th and the 5th observations, so first you have to order the data from least to greatest:

25; 32; 34; 40; 47; 50; 60; 61

The Median is between 40 and 47 ºF, so you have to calculate the average between these two values:

[tex]Me= \frac{(40+47)}{2} = 43.5[/tex] ºF

The correct option is D.

I hope this helps!

Answer:

it is d

Step-by-step explanation:

Answer:

Step-by-step explanation:

Let X be the amount of cashews that the nutty professor will mix.

Since, the total weight of the nuts should be 35 lbs

The amount of Brazil nuts = 35 - X

Now,

[tex]6x + 5.30(35 - x) = 5.64(35)[/tex]

[tex]600x + 530(35 - x) = 564 \times 35[/tex]

[tex]600x + 18550 - 530x = 19740[/tex]

[tex]70x = 19740 - 18550[/tex]

[tex]70x = 1190[/tex]

[tex]x = \frac{1190}{70} [/tex]

[tex]x = 17[/tex]

Again,

[tex] 35 - x[/tex]

[tex]35 - 17[/tex]

[tex]18[/tex]

17 pounds of cashew and 18 pounds of Brazil nuts.

Hope this helps...

Good luck on your assignment...

Answer:

B is the answer

Step-by-step explanation:

-3(2w+6)-4

-6w-18-4

-6w-22

Answer:

Step-by-step explanation:

-3(2w + 6) - 4

1. Distribute

 = -3*2w = -6w

 = -3 * 6 = -18

 = -6w -18

2. Simplify like terms

 = -18 - 4

 = -22

3. Place variables and numbers together

 = -6w - 22

Explanation:

2 * -3w = -6w

2*-11 = -22

Place them together and you get the answer!

Answer:

x = -2 , -1

Step-by-step explanation:

Set the equation equal to 0. Add 2 to both sides:

x² + 3x = -2

x² + 3x (+2) = - 2 (+2)

x² + 3x + 2 = 0

Simplify. Find factors of x²  and 2 that will give 3x when combined:

x²  + 3x + 2 = 0

x               2

x               1

(x + 2)(x + 1) = 0

Set each parenthesis equal to 0. Isolate the variable, x. Note that what you do to one side of the equation, you do to the other.

(x + 2) = 0

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

x = 0 - 2

x = -2

(x + 1) = 0

x + 1 (-1) = 0 (-1)

x = 0 - 1

x = -1

x = -2 , -1

~

Answer:

x = -2       OR      x = -1

Step-by-step explanation:

=> [tex]x^2+3x = -2[/tex]

Adding 2 to both sides

=> [tex]x^2+3x+2 = 0[/tex]

Using mid-term break formula

=> [tex]x^2+x+2x+2 = 0[/tex]

=> x(x+1)+2(x+1) = 0

=> (x+2)(x+1) = 0

Either:

x+2 = 0    OR     x+1 = 0

x = -2       OR      x = -1

P.S. Ummmm maybe...... Because he usually reports absurd answers! So, Won't it be better that he could directly delete it. And one more thing! He's Online 24/7!!!!!

Answer:

width of a river = 45m

Step-by-step explanation:

ration and proportion

let x = width of a river

x            20.9 m

------  =    --------

56 m       26 m

x = (20.9 * 56) / 26

x = 45 m

therefore the width of a river is 45 m

Answer:

No. At a significance level of 0.1, there is not enough evidence to support the claim that the bags are underfilled (population mean significantly less than 418 g.)

Step-by-step explanation:

This is a hypothesis test for the population mean.

The claim is that the bags are underfilled (population mean significantly less than 418 g.)

Then, the null and alternative hypothesis are:

[tex]H_0: \mu=418\\\\H_a:\mu< 418[/tex]

The significance level is 0.1.

The sample has a size n=9.

The sample mean is M=413.

As the standard deviation of the population is not known, we estimate it with the sample standard deviation, that has a value of s=20.

The estimated standard error of the mean is computed using the formula:

[tex]s_M=\dfrac{s}{\sqrt{n}}=\dfrac{20}{\sqrt{9}}=6.6667[/tex]

Then, we can calculate the t-statistic as:

[tex]t=\dfrac{M-\mu}{s/\sqrt{n}}=\dfrac{413-418}{6.6667}=\dfrac{-5}{6.6667}=-0.75[/tex]

The degrees of freedom for this sample size are:

[tex]df=n-1=9-1=8[/tex]

This test is a left-tailed test, with 8 degrees of freedom and t=-0.75, so the P-value for this test is calculated as (using a t-table):

[tex]\text{P-value}=P(t<-0.75)=0.237[/tex]

As the P-value (0.237) is bigger than the significance level (0.1), the effect is not significant.

The null hypothesis failed to be rejected.

At a significance level of 0.1, there is not enough evidence to support the claim that the bags are underfilled (population mean significantly less than 418 g.)

Answer:

the answer is b

Step-by-step explanation:

Answer:

See explanation

Step-by-step explanation:

To determine whether each of these functions is [tex]O(x^2)[/tex], we apply these theorems:

(a)Given the function: f(x)=100x+1000

The highest power of n is 1.

Therefore f(x) is O(x).

Since any O(x) function is always [tex]O(x^2)[/tex], 100x+1000 is [tex]O(x^2)[/tex].

[tex](b) f(x)=100x^ 2 + 1000[/tex]

The highest power of n is 2.

Therefore the function is [tex]O(x^2)[/tex].

Answer:

i think its 2000

Step-by-step explanation:

Answer: 29,000.00

Step-by-step explanation:

Let the income=x.  22%=0.22.

So 6380/x=0.22

x=6380/0.22=29,000.00

Answer:

SAS

Step-by-step explanation:

ΔABD ~ ΔECD is similar through:

S - because ED = CD (Given)

A - same angle ∠D (Statement 2)

S - because AD = BD (Given)

Cheers!

Answer:

SAS

Step-by-step explanation:

Answer:

1080

Step-by-step explanation:

first do 3 times 1800, because they are both the numerators. Then divide that number, which is 5400, by the denominator: 5. You will get 1080.

Answer:

1

Step-by-step explanation:

The range is the output values

The only output value is y=1

The range is 1

Answer:a. ii.

A. Is Theoretical because there is no real way of knowing what you will roll.

Answer:

a. 0.17

b. 0.08

c. theoretical

Step-by-step explanation:

Answer:

width = 4.5 m

length = 14 m

Step-by-step explanation:

okay so first you right down that L = 5 + 2w

then as you know that Area = length * width so you replace the length with 5 + 2w

so it's A = (5 +2w) * w = 63

then 2 w^2 + 5w - 63 =0

so we solve for w which equals 4.5 after that you solve for length : 5+ 2*4.5 = 14