Question

The area of a rectangle is 2916.The ratio of the width to the length is 4 colon 9.The perimeter of the rectangle is

Answer 1

Okay, so let's look at the ratio first. If we set a variable like "n" to be the amount of length and width.

A = lw
2916 = (4n)(9n)

Does making that equation make sense?

Answer 2

yes

Answer 3

So if you multiplied the two terms on the right side and isolate for n, what do you get?

Answer 4

36n

Answer 5

In this case, it would be 36n^2, because that gets multiplied too.

Answer 6

ok

Answer 7

So what you have now is 2916 = 36n^2.

Do you know how to get n by itself now?

Answer 8

do you divide 2916 by 36?

Answer 9

Yup, so that gives you

81 = n^2

What next?

Answer 10

not sure

Answer 11

So right now, in order to get "n" by itself, you need to get rid of that ^2, or squared function. What's the opposite to squaring?

Answer 12

taking the square root?

Answer 13

Yeah, so you would do like that so:\[\sqrt{81} = \sqrt{n ^{2}}\]\[9 = n\] Does everything make sense up until this step?

Answer 14

yes I forget that last step

Answer 15

Alright, so now you know the value of "n", what did we say about the ratio of length to width and how they are related to n?

Answer 16

2916=(4n)(9n)

Answer 17

Yeah, so you know width = 4n, and length = 9n. Use the value of n we just got to find out the width and length

Answer 18

so I would do 4*9 and 9*9

Answer 19

which is 36 and 81then I would do 2(36) 2(81)

Answer 20

so p=234

Answer 21

Yeah, nice job

Answer 22

Thank you!! I always forget the squaring part