Question

The length of a rectangle is 8 cm more than 3 times its width. The perimeter of the rectangle is 64 cm. Show the equation that would be used to find the dimensions of the rectangle.

Let w = the width. Then 3(w + 8) = length. So the equation is 64 = 2(3(w + 8)) + 2w.

Let w = the width. Then 3w = length + 8. So the equation is 64 = 2(3w – 8) + 2w.

Let w = the width. Then 3w + 8 = length. So the equation is 64 = 2(3w + 8) + 2w. 64 = 2(3w + 8) + 2w

Let w = the width. Then 3w + 8 = length. So the equation is 64 = (3w + 8) w.

Answer 1

Let w = the width. Then 3w + 8 = length. So the equation is 64 = 2(3w + 8) + 2w.

Explanation:

This is the correct answer because it satisfies both parts of the statement.

Firstly, we know that the length is 3 times the width plus 8. This gives us that answer. Those with the parenthesis would need to be distributed and would actually wind up being 3w + 24. Therefore those are not correct.

Also, the equation for perimeter is 2l + 2w. If we use that formula and put in the value we have above for length, we get the correct answer.