help with khan academy

this is best solved using algebra

let the width be 4x (since it is 4 times more the length)

let the length be x

the formula for perimeter is (l+b)2 let us sub these variables in our formula

(x + 4x)2 = 64

expand brackets

2x + 8x = 64

combine like terms

10x = 64

make x the subject

x = 64/10 = 6.4

the length is 6.4 m

now let's find the width, the width is 4 times more the length so we simply substitute our value we found for x in 4x

we get:

4(6.4) = 25.6

the length is 25.6m

let's check our answers to see if its correct

25.6 + 6.4 = 32

32 × 2 = 64

the answer is correct

Answer:

3p² + 32p + 13

Step-by-step explanation:

Okay, so lets first solve for 2b. 2b = 2(p + 5), which is equal to 2p + 10. Now, let's solve for 3a. 3a = 3(p² + 10p +1), simplifying to 3p² + 30p +3. After adding 2b and 3a, we are able to get 2p + 10 + 3p² + 30p + 3 = 3p² + 32p + 13

Answer:

3p² + 32p + 13

Step-by-step explanation:

3p² + 32p + 13

Answer:

Good luck on the test <333

Step-by-step explanation:

m<1 = ? // m<2 = ? // m<3 = ? // m<4 = ?

First I want to find the third angle because I see 93 degrees + 3 equals 180, so angle 3 is 87.

Now I find angle 2, because it seems as angle 2 is the same as 49 degrees.

Now for angle 1 and 4, we now that angles in a triangle sum to 180°. So for angle 1 the equation is 180 - (49 + 68), which is 63.

For angle 4 the equation is 180 - (49 + 87), which is 44.

Answer:

-217 is the answer.

Step-by-step explanation:

negative nineteen is -19

eleven = 11

and from their product we have to subtract 8.

so,

-19×11

= -209

-209-8

= -217.

hope it helps you

plzz plzz plzz mark as brainliest

Answer:

the number is -1

Step-by-step explanation:

Let the number be x. PROOF

11x-8=-19. (11×-1)-8=-19

11x=-19+8

11x=-11

11x/11=11/11

x=1

Answer:

x - 5 = 0

Step-by-step explanation:

x - 5 = 0

Add 5 on both sides,

x - 5 + 5 = 0 + 5

x = 5

The equation whose solution is 5,

" x - 5 = 0 "

Answer:

x-5=0 right answer

kkkkkksssxcvbb

Answer:

The Cardinality of this set {7,8,9} is n(P) = 8.

Step-by-step explanation:

Because:

n(P) = {{}, {7}, {8}, {9}, {7, 8}, {8, 9}, {7, 9}, {7, 8, 9}}

Hence by the formula 2^k.

where, k = number of elements in the set.

The cardinality is 8.

Answer:

In order to multiply rational expressions:

Step 1: Completely factor all numerators and denominators.

Step 2: Reduce all common factors.

Step 3: Either multiply the denominators and numerators or leave the answer in factored form.

Here is an example:

Answer:

[tex]solution 1: \ \frac{7+\sqrt{65}}{2};[/tex]

[tex]solution2: \ \frac{7-\sqrt{65} }{2}.[/tex]

Step-by-step explanation:

x²-7x-4=0;

D=[b²-4ac]=49+16=65.

[tex]\left[\begin{array}{ccc}x=\frac{7+\sqrt{65}}{2} \\x=\frac{7-\sqrt{65}}{2} \end{array}[/tex]

Answer:

The price of the comic book would be $2.79 after the discount and the tax.

We first take 10% of 2.95 or 0.295 from 2.95 to get our first value of 2.66.

Then we add 5% of 2.66 or 0.133 back to 2.66 to get our last value of 2.79.

Step-by-step explanation:

hope this helps. . . <3

good luck!    uωu

Answer:

[tex]\sf{Exact\:form:\\\sqrt[4]{81}\\[/tex]

[tex]\bold{Decimal\:form:-3}[/tex]

Step-by-step explanation:

[tex]-81^\frac{1}{4}[/tex]

[tex]\mathrm{Convert\: to\: radical\: form\: using\: the\: formula\:}\: a^\frac{x}{n} = \sqrt[n]{a^x}[/tex]

[tex]\mathrm{If\:} n \mathrm{\:is\: a\: positive\: integer\: that\: is\: greater\: than\:} x\mathrm{\:and\:} a \mathrm{\:is\: a\: real\: number\: or\: a\: factor, then} \\a^\frac{x}{n} = \sqrt[n]{a^x}[/tex]

[tex]\mathrm{Use\: the\: rule\: to\: convert\: -81^\frac{1}{4}\: to\: a\: radical, where\:} a=-81,\ x=1, \mathrm{and\:} n=4\\\sqrt[4]{81}[/tex]

[tex]\mathrm{Plug\: the\: points:}\\\\a^\frac{x}{n} = \sqrt[n]{a^x}\\-81^\frac{1}{4} =\sqrt[4]{81}[/tex]

[tex]\mathrm{Solve}\\\\\mathrm{The\: result\: can\: be\: shown\: in\: multiple\: forms.}[/tex]

Answer:

Step-by-step explanation:

x = 35° (opposite agles)

y = 180 - 35 - 75

y = 70

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

check 35 + 75 + 70 = 180°

the answer is good

Answer:

He will have 8 50-cent coins

Step-by-step explanation:

Let x = the number of 10-cent coins

Let y = the number of 50-cent coins

x + y = 20         y = 20 - x

[Set up an equation] .10x + .50y = 6.80

[Multiply both sides by 100] 10x + 50y = 680

[Plug-in] 10x + 50(20 - x) = 680

[Multiply] 10x + 1,000 - 50x = 680

[Combine like terms & subtract 1,000 from both sides] -40x = -320

[Divide both sides by -40] x = 8 coins

Have a nice day! - hopefully this is correct, I got a bit turned around for a bit lol

     I hope this is what you are looking for, but if not - comment! I will edit and update my answer accordingly. (ノ^∇^)

- Heather

Step-by-step explanation:

To multiply fractions:

Multiply numerator to numerator and multiply denominator to denominator. Simplify the answer.

To multiply mixed numbers:

Change mixed numbers into improper fraction. Then multiply numerator and denominator just like how you multiply the fractions. Simplify.

Answer:

x=4

Step-by-step explanation:

Answer:

16

Step-by-step explanation:

the square root of 16 is 4. (4x itself is 16)

out of the options, that is the only one that has a whole number as the square root.

Answer:

24-8=t

Step-by-step explanation:

I cant really explain much...

but, Hope it helps

plz mark brainiest if it does

Answer:

[tex]-54x^8[/tex]

Step-by-step explanation:

[tex]2x^2(-27)x^6\\\\-54x^2x^6\\\\-54x^{2+6}\\\\-54x^8[/tex]

Answer:

Step-by-step explanation:

Solve each to confirm answer

a.

b.

c.

d.

Answer:

Option B

Step-by-step explanation:

[tex]\\ \sf\longmapsto x^2-2x+2=0[/tex]

[tex]\\ \sf\longmapsto x=\dfrac{-(-2)\pm\sqrt{(-2)^2-4(1)(2)}}{2(1)}[/tex]

[tex]\\ \sf\longmapsto x=\dfrac{2\pm\sqrt{4-8}}{2}[/tex]

[tex]\\ \sf\longmapsto x=\dfrac{2\pm\sqrt{-4}}{2}[/tex]

[tex]\\ \sf\longmapsto x=\dfrac{2\pm 2i}{2}[/tex]

[tex]\\ \sf\longmapsto x=1\pm i[/tex]

Verified

Answer:

We don't have the tax rate so I'll just explain how to do it

Step-by-step explanation:

158,500 multiplied by ( a unit of one subtracted (-) from the percentage of tax rate in decimal form ) is the total of money Miranda made after tax

Answer:

80

Step-by-step explanation:

1 pizza has 8 [tex]\frac{1}{8}[/tex]ths. 10 pizzas have 10 × 8 = 80 1/8ths. So 80.

Answer:

80 because if one student gets 1/8 that means 8 students get one slice out of the pizza multiply 8 by 10 and it equals 80

Answer:It's easy for us to visualize a meter; that's about 3 feet. ... nm (10-9 m) to 100 nanometers (100 x 10-9 = 10-7 m) and the unique properties that arise.

Step-by-step explanation:

Answer:

25-10  (25 - A and 10 - B)

Step-by-step explanation:

25 - 10 equals the 15 point margin

25 plus 10 equals the 35 point score combined

Hope it helps

Answer:

25 to 10

First of all, you'd have to write an equation.

            35                   =       (x+15)        +    x

total number of points       Team A         Team B

Subtract 15 from both sides.

20 = 2x

Divide.

20/2 equals X=10

Then you would add 15 to 10 and that would be Team A's score, therefore 25, Team B's is 10.

Answer:

Between 6 & 7

Step-by-step explanation:

The square root of 45 is 6.7. So it'll be between 6 & 7.

Using error concepts for hypothesis tests, it is found that there is a Type I error.

A Type I error happens when a true null hypothesis is rejected.

A Type II error happens when a false null hypothesis is not-rejected.

In this problem, the null hypothesis is:

[tex]H_0: \mu = 24[/tex]

The alternative hypothesis is:

[tex]H_1: \mu > 24[/tex]

He concludes that the mean age is over 24 when it is not, that is, a true null hypothesis is rejected, hence there is a Type I error.

A similar problem is given at https://brainly.com/question/25225353

Answer:

of which class is it ?

Step-by-step explanation:

???????.................

answer:

1

Step-by-step explanation:

#'s between zero and two = one

the only number between 0 and two is 1

x = 1  y = 1  z = 1

the average value of the sum of the squares of x, y and z = 1

1, 1, 1

the average is 1

Answer:

Not a linear function

Step-by-step explanation:

3xy = 27 is not a linear function.

A linear function is given by f(x) = mx + b (in slope-intercept form), or Ax + By = C (in standard form).   An easier way of understanding the linear function is to envision that the variables (x and y), along with the constant,(y-intercept, are along the same line.  

Isolating y from the left-hand side:

3xy = 27  

On the left-hand side of the equation: 3xy involves a multiplication operation. Thus, 3xy  is the same as expressing it as  3·x·y.  

We cannot simply add or subtract x or y to isolate either one of the variables.  The proper mathematical operation to do so is by division.

Hence, we must divide both sides by 3x to isolate y:

[tex]\displaystyle\mathsf{\frac{3xy}{3x}\:=\:\frac{27}{3x}}[/tex]

[tex]\displaystyle\mathsf{y\:=\:\frac{9}{x}}[/tex]   ⇒ This is a reciprocal function, also known as an inverse function, where it is undefined when x = 0.  The graph of an inverse function is a hyperbola.      

Attached is the graph of  [tex]\displaystyle\mathsf{y\:=\:\frac{9}{x}}[/tex]  to show why it is not considered as a linear function. A linear function will show a straight line.  

Answer:

Step-by-step explanation:

(3x)² + (4x)² = 20²

9x² + 16x² = 400

25x² = 400

x² = 16

x = 4

height = 3(4) = 12 inches

width = 4(4) = 16 inches