Zack computes the perimeter of a rectangle by adding the length, l, and width, w, together, then doubling the sum. rachel computes the perimeter by doubling the length and doubling the width and then adding the doubled amounts. i'll mark the brainliest!

Part A:

So Zack's method of calculating the perimeter of a rectangle is by adding the length and the width first, which means we have:

=> L + W

AND then he double the sum that we already got above or in other words, multiply it by 2, which will give us the final expression: 2 · (L + W)

Part B:

So Rachel took a slightly different approach. She first doubles the length as well as the width, which will give us 2L AND 2W.

THEN she adds the doubled amounts (which are 2L and 2W) which will give us the final expression: 2L + 2W

*If you notice, you can see that 2L + 2W is also equal to 2(L + W), so both of them will give us exactly the same result.