the ratio of the side lengths in a rectangular is 5: 2: 5: 2, and its area is 90 square feet. find the side lengths

Answer 1

Hello, Alyzah,

Area (A) is W*L. , where L is length and W is width.

I'll assign the length (L) to be the longer of the two. That means the length is L = (5/2)W

Now we can make a substitution by using (5/2)W in place of L in the area equation:

If A = W*L

then A also = W*(5/2)W,

or A = (5/2)W²

A is 90 ft², so we have:

90ft² = 2.5W²

W² = 36ft²

W = 6ft [that step was easy - thanks]

We then can calculate L:

90ft² = 6L

L = 15ft

Bob