PLEASE HELP Give me an example of a negative correlation

Answer:

Domain: all real numbers/ (-inf,inf)/ -inf<x<inf

Range: all real numbers greater than -4/  [-4,inf)/ -4≤y<inf

Step-by-step explanation:

the graphs/equations of ALL quadratics (parabolas) have a domain of all real numbers

The vertex of the parabola is at y=-4 so the range cannot be any less than that, and then both ends point up, so they will continue on for infinity.  

Hope i could help!

Answer:

3,440 strawberries

Step-by-step explanation:

Because of PEMDAS you want to start with the parentheses, and want to treat them like the distributive property.

So,

43 x 2 = 86

Then,

86 x 40 = 3440.

I hope that helps!!

Answer: 3440 strawberries on the farm.

Step-by-step explanation: (43)(2)⋅40                                                                     (86)(40)                                                                                                                     3440

Answer:

The answer is below

Step-by-step explanation:

Expansion using pascal triangle:

a)  (x + 2)⁶ = x⁶2⁰ + 6(x⁵)(2)¹ + 15(x⁴)(2²) + 20(x³)(2³) + 15(x²)(2⁴) + 6(x)(2⁵) + 1(2⁶)

                 = x⁶ + 12x⁵ + 60x⁴ + 160x³ + 240x² + 192x + 64

b) (x-4)⁴ = x⁴ + 4(x³)(-4) + 6(x²)(-4)² + 4(x)(-4)³ + 1(x⁰)(-4)⁴

              =x⁴-16x³+96x²-256x+256

c) (2x + 3)⁵ = (2x)⁵ + 5(2x)⁴(3) + 10(2x)³(3)² + 10(2x)²(3)³ + 5(2x)(3)⁴ + 1(2x)⁰(3)⁵ =

                  = 32x⁵ + 240x⁴ + 720x³ + 1080x² + 810x + 243

d) (2x-3y)⁴ = 1(2x)⁴(-3y)⁰ + 4(2x)³(-3y) + 6(2x)²(-3y)² + 4(2x)(-3y)³ + 1(2x)⁰(-3y)⁴

                  = 16x⁴- 96x³ + 216x² - 216x + 81

Expansion using binomial where [tex]C(n,r)=\frac{n!}{(n-r)!r!}[/tex]

a)  (x + 2)⁶ = C(6,0)[x⁶2⁰] + C(6,1)[(x⁵)(2)¹] + C(6,2)[(x⁴)(2²)] + C(6,3)[(x³)(2³)] + C(6,4)[(x²)(2⁴)] + C(6,5)[(x)(2⁵)] + C(6,6)[(2⁶)]

                = x⁶2⁰ + 6(x⁵)(2)¹ + 15(x⁴)(2²) + 20(x³)(2³) + 15(x²)(2⁴) + 6(x)(2⁵) + 1(2⁶)

                 = x⁶ + 12x⁵ + 60x⁴ + 160x³ + 240x² + 192x + 64

b) (x-4)⁴ = C(4,0)[x⁴] + C(4,1)[(x³)(-4)] + C(4,2)[(x²)(-4)²] + C(4,3)[(x)(-4)³] + C(4,4)[(x⁰)(-4)⁴]

              = x⁴ + 4(x³)(-4) + 6(x²)(-4)² + 4(x)(-4)³ + 1(x⁰)(-4)⁴

              =x⁴-16x³+96x²-256x+256

c) (2x + 3)⁵   = C(5,0)[(2x)⁵] + C(5,1)[(2x)⁴(3)] + C(5,2)[(2x)³(3)²] + C(5,3)[(2x)²(3)³] + C(5,4)[(2x)(3)⁴] + C(5,5)[(2x)⁰(3)⁵]

                   = (2x)⁵ + 5(2x)⁴(3) + 10(2x)³(3)² + 10(2x)²(3)³ + 5(2x)(3)⁴ + 1(2x)⁰(3)⁵

                  = 32x⁵ + 240x⁴ + 720x³ + 1080x² + 810x + 243

d) (2x-3y)⁴ = C(4,0){(2x)⁴(-3y)⁰} + C(4,1)[(2x)³(-3y)] + C(4,2)[(2x)²(-3y)²] + C(4,3)[(2x)(-3y)³] + C(4,4)[(2x)⁰(-3y)⁴]

                  = 1(2x)⁴(-3y)⁰ + 4(2x)³(-3y) + 6(2x)²(-3y)² + 4(2x)(-3y)³ + 1(2x)⁰(-3y)⁴

                  = 16x⁴- 96x³ + 216x² - 216x + 81

In the expansion of (3a + 4b)⁸, the only possible variable terms are a⁵b³, b⁸, a⁴b⁴, a⁸, ab⁷ because for each of them, the sum of there powers is eight. If the sum of the powers is not 8 then it is not correct.

For a²b³, the sum of the power is 5, for ab⁸ the sum of power is 9 and for a⁶b⁵ the sum of the power is 11 therefore thy are not correct.

As per the question expand the bimonoidal theorem and the pascal triangle. Showing the (x+2)6 (x-4)4 (2x+3)5 (2x-3y)4.

Learn more about the use the binomial theorem.

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Answer:

29

Step-by-step explanation:

conjugate of a+ib=a-ib

conjugate of 2-5i=2+5i

(2+5i)(2-5i)=2²-(5i)²=4-25i²=4-25(-1)=4+25=29

Answer:

29

i had the same question and 29 was the right answer

Answer:

4 maximum extrema

Step-by-step explanation:

5th degree means that it can change direction 5 times, therefore creating a maximum of 4 extrema

Answer:

4 hrs

Step-by-step explanation:

half of Jim Rollers time is 1.5 hrs, and half of John Brushs time is 2.5 hrs. The two combined is 4 hrs. Therefore, the answer is four hours.

This is basically finding the average of two numbers, and you can use multiple different equations to find the same answer.

3/2 + 5/2 =4

(3+5)/2 =4

5-3=2, then 2/2=1, 5-1=4

Answer:

1 7/8 hours

Step-by-step explanation:

Answer:

y = 3x+13

Step-by-step explanation:

y-3x=13

Add 3x to each side

y-3x+3x=3x+13

y = 3x+13

The value of y for the given equation y - 3x = 13 is calculated to be y = 3x + 13.

Given that:

y - 3x = 13

It is required to find the value of y.

In order to find the value of y, the equation has to be solved in such a way that y has to be kept on one side.

Consider:

y - 3x = 13

Add 3x on both sides.

y - 3x + 3x = 13 + 3x

y = 13 + 3x

Hence, the value of y is 13 + 3x.

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Answer:

[tex]-40c^{2} d^{2} -32cd[/tex]

Step-by-step explanation:

-20c³ is the expression which is equivalent to (-5cd⁻⁴)(2cd²)².

To simplify the given expression, (-5cd⁻⁴)(2cd²)², we can apply the power of a product rule, which states that (ab)² is equal to a²b².

Let's break down the expression step by step:

(-5cd⁻⁴)(2cd²)²

First, let's square the expression (2cd²)²:

(2cd²)² = (2)²(c)²(d²)² = 4c²d⁴

Now, we substitute this result back into the original expression:

(-5cd⁻⁴)(4c²d⁴)

To simplify further, we can multiply the coefficients and combine the variables:

(-5)(4) = -20

(c)(c²) = c³

(d⁻⁴)(d⁴) = 1

Putting it all together, the expression (-5cd⁻⁴)(2cd²)² simplifies to -20c³.

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Answer:

1.18 dollar.

Step-by-step explanation:

E = 17/20D

E => The amount in euros.

D => The amount in dollars.

From the question given,

E = 1

D =?

E = 17/20D

1 = 17/20D

Cross multiply

20 x 1 = 17D

20 = 17D

Divide both side by 17

D = 20/17

D = 1.18

Therefore, 1.18 dollar is equivalent to 1 euro.

Answer:

How many Euros have the same value as 1 U.S. dollar?

17/20 euros

How many U.S. dollars have the same value as 1 euro?

59/50 dollars

(or 0.85 either one is correct)

Step-by-step explanation:

Khan Academy

Hope this helps! ;)

Answer:

see below

Step-by-step explanation:

1) (2/4w)⁴

The product of two over four and w, to the fourth power.

2) x/9

The quotient of x and 9.

3) 3/5 (3 - x)

The product of three over five and the difference of 3 and x.

Answer:

See below

Step-by-step explanation:

1) The quotient of 2 and four times w to the 4th power

2) The quotient of x and 9

3) The quotient of 3 and 5 multiplied with the difference of 3 and x.

Answer:  A

Step-by-step explanation:

Notes: Dividing by a fraction means to multiply by its reciprocal.

           The denominator cannot equal zero.

[tex]\dfrac{5a^3bc}{8ab^3}\div\dfrac{-ab^2}{6a^5b}\cdot \dfrac{2a^2b^3}{3b}\qquad \rightarrow a\neq 0,b\neq 0\\\\\\=\dfrac{5a^3bc}{8ab^3}\cdot\dfrac{6a^5b}{-ab^2}\cdot \dfrac{2a^2b^3}{3b}\\\\\\=\dfrac{5\cdot 6\cdot 2\quad a^3\cdot a^5\cdot a^2\quad b\cdot b\cdot b^3\quad c}{8\cdot -1 \cdot 3\quad a\cdot a\qquad b^3\cdot b^2\cdot b \quad}\\\\\\=\dfrac{-60a^{10}b^5c}{-24a^2b^6}\\\\\\=\dfrac{-5a^8c}{2b}[/tex]

Answer:

He cut 6 slices

3/4 (leftover bread) equals to six eights (6/8)

Answer:

B

Step-by-step explanation:

The rules for reflecting across the x axis are just multiply the y value by -1

your answer is the second answer choice

For y axis refection, it is the same but for the x value, not the y .

Answer:

18 feet

Step-by-step explanation:

to find the frame around the widow means need to find the perimeter around the window:

P=2l+2w

P= 2(5+4)

P=18 feet

Answer:

Exact form:

25/9

Decimal form:

2.(7)

Mixed fraction form:

2 7/9

Step-by-step explanation:

Hope you found this helpful

Answer:

(-5/3)² = 25/9

Step-by-step explanation:

(a/b)ⁿ = aⁿ / bⁿ

(-5/3)² = -5² / 3² = 25 / 9

Answer:

two games must be won by the team

Step-by-step explanation:

Let the no. of games played by x, since  team

does not lose any more games.

Then total game won = 6+x

total game lost = 4

win: loss = 6+x : 4

given ratio of win and loss = 2:1

6+x : 4 = 2: 1

6+x = 8

=> x = 8-6 = 2

Thus, two games must be won by the team

then total win will be = 6+2 = 8

and loss = 4

ration of win : loss = 8:4 = 2:1

522km / 36= 14.5km PER litre

14.5 x 14= 203

Answer:

100, 101, 102, 103, 104

Step-by-step explanation:

Basically, if the units (or ones, it's the same thing) digit of the first number is 0, the units digit of the second number should be 1, then 2, and so on. Therefore, one possible list of numbers is as follows: 100, 101, 102, 103, 104.

Answer:

D

Step-by-step explanation:

-4xy

will be your answer after factoring

Answer:

d

Step-by-step explanation:

Given

(x - y)² - (x + y)² ← expand both factors using FOIL

= x² - 2xy + y² - (x² + 2xy + y²) ← distribute by - 1

= x² - 2xy + y² - x² - 2xy - y² ← collect like terms

= - 4xy → d

Answer:

a. [tex]\mathbf{P(Y \leq 60) = 0.3333}[/tex]

b. P(Y>50) = 0.8889

c. E(y) = 67.5 and  Standard deviation [tex]\sigma[/tex] = 12.99

Step-by-step explanation:

From the information given :

an automobile body paint shop, has determined that the painting time of automobiles is uniformly distributed and that the required time ranges between 45 minutes to [tex]1\frac{1}{2}[/tex]hours.

The objective is to determine  the probability that the painting time will be less than or equal to an hour?

since 60 minutes make an hour;

[tex]1\frac{1}{2}[/tex]hours = 60 +30 minutes = 90 minutes

Let Y be the painting time of the automobile; then,

the probability that  the painting time will be less than or equal to an hour ca be  computed as :

[tex]P(Y \leq 60) = \int ^{60}_{45} f(y) dy \\ \\ \\ P(Y \leq 60) = \int ^{60}_{45} \dfrac{1}{45} dy \\ \\ \\ P(Y \leq 60) = \dfrac{1}{45} \begin {pmatrix} x\end {pmatrix}^{60}_{45} \\ \\ \\ P(Y \leq 60) = \dfrac{60-45}{45 } \\ \\ \\ P(Y \leq 60) = \dfrac{15}{45} \\ \\ \\ P(Y \leq 60) = \dfrac{1}{3} \\ \\ \\ P(Y \leq 60) = 0.3333[/tex]

What is the probability that the painting time will be more than 50 minutes?

The probability that the painting will be more than 50 minutes is P(Y>50)

So;

[tex]P(Y>50) = \int \limits ^{90}_{50} f(y) dy[/tex]

[tex]P(Y>50) = \int \limits ^{90}_{50} \dfrac {1}{45} dy[/tex]

[tex]P(Y>50) = \dfrac{1}{45}[x]^{90}_{50}[/tex]

[tex]P(Y>50) = (\dfrac{90-50}{45})[/tex]

[tex]P(Y>50) = \dfrac{40}{45}[/tex]

P(Y>50) = 0.8889

Determine the expected painting time and its standard deviation.

Let consider E to be the expected painting time

Then :

[tex]E(y) = \int \limits ^{90}_{45} y f(y) dy \\ \\ \\ E(y) = \int \limits ^{90}_{45} y \dfrac{1}{45} dy \\ \\ \\ E(y) = \dfrac{1}{45} [\dfrac{y^2}{2}]^{90}_{45} \\ \\ \\ E(y) = \dfrac{1}{45}[\dfrac{(90^2-45^2)}{2}] \\ \\ \\ E(y) = \dfrac{1}{45} (\dfrac{6075}{2}) \\ \\ \\ E(y) = \dfrac{1}{45} \times 3037.8 \\ \\ \\ \mathbf{E(y) = 67.5}[/tex]

[tex]E(y^2) = \int \limits ^{90}_{45} y^2 f(y) dy \\ \\ \\ E(y^2) = \int \limits ^{90}_{45} y^2 \dfrac{1}{45} dy \\ \\ \\ E(y^2) = \dfrac{1}{45} [\dfrac{y^3}{3}]^{90}_{45} \\ \\ \\ E(y^2) = \dfrac{1}{45}[\dfrac{(90^3-45^3)}{3}] \\ \\ \\ E(y^2) = \dfrac{1}{45} (\dfrac{637875}{3}) \\ \\ \\ E(y^2) = \dfrac{1}{45} \times 2126.25 \\ \\ \\ \mathbf{E(y^2) = 4725}[/tex]

To determine the standard deviation, we need to first know what is the value of our variance,

So:

Variance [tex]\sigma^2[/tex] = E(x²) - [E(x)]²

Variance [tex]\sigma^2[/tex] = 4725 - (67.5)²

Variance [tex]\sigma^2[/tex] = 4725 - 4556.25

Variance [tex]\sigma^2[/tex] = 168.75

Standard deviation [tex]\sigma[/tex] = [tex]\sqrt{variance}[/tex]

Standard deviation [tex]\sigma[/tex] = [tex]\sqrt{168.75}[/tex]

Standard deviation [tex]\sigma[/tex] = 12.99

Answer:

64 mph

Step-by-step explanation:

Given that:

Speed for the first 3 hours = 52 mph

Average speed for 4 hours = 55 mph

To find:

Speed for the next hour = ?

Solution:

Formula for average speed is given as:

[tex]Average\ Speed = \dfrac{Total\ Distance}{Total \ Time \ Taken}[/tex]

Formula for Distance:

[tex]Distance =Speed \times Time[/tex]

Distance traveled in first 3 hours:

[tex]Distance =52\times 3 = 156\ miles[/tex]

Let the speed for the next hour = u mph

Distance traveled in 1 hour = [tex]u \times 1 = u\ miles[/tex]

Total distance traveled = (156 + u) miles

Total time = 4 hours

Average Speed = 55 mph

Putting the values in formula:

[tex]55 = \dfrac{156+u}{4}\\\Rightarrow 220 = 156+u\\\Rightarrow \bold{u = 64\ mph }[/tex]

So, the answer is: 64 mph

Answer:

Step-by-step explanation:

In this problem we are required to find the cost of the laptop when 9.25% of the cost is added as tax

we are given that the tax rate is 9.25% of the initial cost

and the initial cost is $703.98

 let us calculate 9.25% of  $703.98

(9.25/100)* 703.98= 0.0925*703.98= $65.12

Hence the charges for tax is $65.12

The total cost of the laptop when tax is included is

the initial cost Plus the tax charges= $703.98+$65.12= $769.098

$769.10

Answer:

15/4 x-y=-24

Step-by-step explanation:

the standard form is ax+by=c

two points (x1,x2) , (y2,y1)

x1=-8       x2=-6

y1=-4        y2=9

find slope m: y2-y1/x2-x1

m=9-(-6)/-4-(-8)

m=15/4

find b: take any point(-8,-6)

y=mx+b

-6=15/4 (-8)+b

-6=-30+b

b=-6+30

b=24

y=15/4 x+24

standard form: y-15/4x=24

OR : 15/4 x-y=-24

Answer:

The shortest altitude is 6.72 cm

Step-by-step explanation:

Given that the side lengths are

24 cm, 25 cm, 7 cm

The area of a triangle =

[tex]A = \sqrt{s \cdot (s-a)\cdot (s-b)\cdot (s-c)}[/tex]

Where;

s = Half the perimeter = (24 + 25 +  7)/2 = 28

A = √((28×(28 - 24)×(28 - 25)×(28 - 7)) = 84 cm²

We note that 84/7 = 12

Therefore, the triangle is a right triangle with hypotenuse = 25, and legs, 24 and 7, the height of the triangle = 7

To find the shortest altitude, we utilize the formula for the area of the triangle A = 1/2 base × Altitude

Altitude  = A/(1/2 ×base)

Therefore, the altitude is inversely proportional to the base, and to reduce the altitude, we increase the base as follows;

We set the base to 25 cm to get;

Area of the triangle A =  1/2 × base × Altitude

84 = 1/2 × 25 × Altitude

Altitude = 84/(1/2 × 25) = 6.72 cm

The shortest altitude = 6.72 cm.

Problem 1.

Yes it is true that vertical angles are congruent, but that's not what your teacher is asking. Instead, your teacher is asking basically how the term "congruent" is defined.

Two segments are congruent if they are the same length. Two angles are congruent if they are the same measure. Two triangles are congruent if they have the same angles and sides.

So in short, "congruent" just means "same". You can think of having mirror copies.

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

Problem 2.

Angles 2 and 4 are one pair of vertical angles. They are opposite one another in this X shape formed by the two lines. The other pair of vertical angles are angle 1 and angle 3.

Angle 2 is given to be 76 degrees, so this means angle 4 is this measure as well.

Angle 1 = 180 - (angle 2) = 180 - 76 = 104, which is also the measure of angle 3 as well. I'm using the idea that the adjacent angles form a straight angle. This is known as a linear pair (ie the angles form a straight line).

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

Problem 3.

If all three angles are the same (all 60 degrees), then we have an equilateral triangle. We could say it's equiangular, but it's also equilateral as well meaning all 3 sides are the same length. "equi" means "equal", "angular" means what you'd expect, and "lateral" means "side".

If only two angles are equal with the third one different, then we have an isosceles triangle. An isosceles triangle is one where only two sides are the same length.

If none of the angles are the same, then we have a scalene triangle. As you probably expect, none of the sides are the same length with a scalene triangle.

----

If all three angles are less than 90 degrees, then the triangle is acute

If one angle is 90 degrees, then we have a right triangle

If one angle is over 90 degrees (but less than 180), then the triangle is obtuse

---

Often you'll see the terms of the previous two sections combined. For instance, we could have an isosceles right triangle. Or we might have an obtuse scalene triangle. Any equilateral triangle is acute (as all three angles are less than 90).

To solve this problem we have to understand what congruent angles are and then find the angles that are congruent to one other in this given question.

Congruent angles are angles that are equal to one another and in the given question, we were given m<2 = 76 degrees.

Data;

If we look critically at the angles, we can use opposite angle theorem here to predict angles that are congruent to another here.

angles 2 and angle 4 are congruent to one another while angle 1 and angle 3 are congruent to one another.

This implies that

Let's solve for other angles.

But the some of angles at a point is equal to 360°

Applying that theorem here,

[tex]m > 1=x\\m > 2 = 72^0\\m > 3 = x\\m > 4 = 72^0[/tex]

Let's substitute the values and solve.

[tex]x+ x + 72+72 = 360\\2x + 144 = 360\\2x = 360 - 144\\2x = 216\\x = \frac{216}{2} \\x = 108^0[/tex]

This can be further summarized as

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Answer:

Quadrilateral

Step-by-step explanation:

Answer:

If the order doesn't matter then we have a combination, if the order do matter then we have a permutation. One could say that a permutation is an ordered combination. The number of permutations of n objects taken r at a time is determined by the following formula: P(n,r)=n!

Step-by-step explanation:

To calculate the probability of a combination, you will need to consider the number of favorable outcomes over the number of total outcomes. Combinations are used to calculate events where order does not matter. In this lesson, we will explore the connection between these two essential topics.

Answer:

combination : If the order of numbers  or  operations does not matter

Permutation : when the order of numbers matter ( common example most teachers use : a code of 4 numbers has to be in a certain order and the numbers are from 0 to 9 , how many permutation can you make if you use the number one time)

P=n!/(n-r)!

n! ( are number from 0-9 we have 10 numbers)

r is the number of digits in the code = 4

n!=10*9*8*7*6*5*4*2*1

(n-r)!=(10-4)!=6!=6*5*4*3*2*1

P=5040 ways ( if the order matter)

If the order does not matter

Combination C(n,r)=n!/(n-r)!r!

C(10,4)=(10*9*8*7*6*5*4*2*1)/[(6*5*4*3*2*1)(4*3*2*1)]

Answer:

x+4

.....................

Answer

[tex] \boxed{x + 4}[/tex]

Option C is the correct option

Step by step explanation

Let's find the expression which represents the length of the box:

[tex] \mathsf{length \times width \times height \: of \: prism \: = \: volume \: of \: prism}[/tex]

[tex] \mathsf{lengh \times \: (x - 1) \times (x + 8) = {x}^{3} + 11 {x}^{2} + 20x - 32}[/tex]

[tex] \mathsf{length = \frac{ {x}^{3} + 11 {x}^{2} + 20x - 32 }{(x - 1)(x + 8)} }[/tex]

Write 11x² as a sum

[tex] \mathsf{ = \frac{ {x}^{3} - {x}^{2} + 12 {x}^{2} + 20x - 32 }{(x - 1)(x + 8)} }[/tex]

Write 20x as a sum

[tex] \mathsf{ = \frac{ {x}^{3} - {x}^{2} + 12 {x}^{2} - 12x + 32x - 32 }{(x - 1)(x + 8)}}[/tex]

Factor out x² from the expression

[tex] \mathsf{ = \frac{ {x}^{2}(x - 1) + 12 {x}^{2} - 12x + 32x - 32 }{(x - 1)(x + 8)} }[/tex]

Factor out 12 from the expression

[tex] \mathsf{ = \frac{ {x}^{2}(x - 1) + 12x(x - 1) + 32x - 32 }{(x - 1)(x + 8)} }[/tex]

Factor out 32 from the expression

[tex] \mathsf{ = \frac{ {x}^{2}(x - 1) + 12x(x - 1) + 32(x - 1) }{(x - 1)(x + 8)} }[/tex]

Factor out x+1 from the expression

[tex] \mathsf{ = \frac{(x - 1)( {x}^{2} + 12x + 32) }{(x - 1)(x + 8)} } [/tex]

Factor out 12x as a sum

[tex] \mathsf{ = \frac{(x - 1)( {x}^{2} + 8x + 4x + 32) }{(x - 1)(x + 8)} }[/tex]

Reduce the fraction with x-1

[tex] \mathsf{ = \frac{ {x}^{2} + 8x + 4x + 32 }{(x + 8)} }[/tex]

Factor out x from the expression

[tex] \mathsf{ = \frac{x(x + 8) + 4x + 32}{(x + 8)} }[/tex]

Factor out 4 from the expression

[tex] \mathsf{ = \frac{x(x + 8) + 4(x + 8)}{x + 8} }[/tex]

Factor out x+8 from the expression

[tex] \mathsf{ = \frac{(x + 8)(x + 4)}{x + 8} } [/tex]

Reduce the fraction with x+8

[tex] \mathsf{ = x + 4}[/tex]

hence, x+4 is the expression that represents the length of a box.

Hope I helped!

Best regards!