The length of a rectangle is 3 inches more than its width. If the perimeter is 42 inches, find the dimensions of the rectangle.

Question

I honestly have ZERO idea on what i'm doing. I can do these types of problems, no big deal. But this doesn't give me an answer to work up to. Like "the sum of the two numbers is 38, find the two numbers." Those I can do. But this doesn't have that and I'm so confused, I don't even know what I'm confused about. 

Answer 1

Greetings! Lets solve this shall we ?

So, we must find the dimensions for the rectangle with the given length of l = x + 3 and width = x with Perimeter = 42 inches. Then, we yield the Perimeter formula such that

2l + 2w = P

2(x+3) + 2(x) = 42............Distribute the 2 such that

2x + 6 + 2x = 42.............Add like terms

4x + 6 = 42..............Then subtract 6 such that

4x = 36.............Then divide 4 such that

x = 9

Then, the width is 9 inches and the length is l = 9+3 = 12 inches.

I hope this helped!