find the dimension

Question

the perimeter of a rectangle is 42. the length is three less than twice width. find the dimension

Answer 1

Let the width be x.
The length will thus be 2x - 3.

Perimeter of rectangle = 42
length + length + width + width = 42
2x - 3 + 2x - 3 + x + x = 42
6x - 6 = 42
6x = 42 + 6
6x = 48
x = 48 / 6
x = 8

When x = 8, we have 2x - 3 = 2(8) - 3 = 16 - 3 = 13

Hence, the dimension of the rectangle is 13 by 8.