Question

Noah and Maggie are making a rectangular picture frame.They want the length of the frame to be three inches longer than the width. If the perimeter is 42”, what are the dimensions of their frame?

Answer 1

9 inches by 12 inches

Explanation:

So let's say L=length and W=width.

Since the problem states that the length should be 3 inches longer than the width, L= W+3

And the formula to find the perimeter of a rectangle is 2L+2W

so plug in W+3 for L and you get 2(W+3)+2W

Then distribute

2W+6+2W

Combine like-terms

4W+6

And the problem states the perimeter is 42 inches so,

4W+6=42

Subtract 6 to both sides

4W=36

Divide by 4 to both sides

W=9

So the width is 9

And to get the length, plug in 9 for W in L=W+3

L=9+3

L=12

So the length is 12