Question

The length of a rectangle is 4 less than 2 times the width. The perimeter is 40 units.

Find the dimensions of the rectangle.
First equation:
Second equation:

Answer 1

Let l be length and w be width.

First equation:

l = 2w-4

Second equation:

perimeter = 40 units

Perimeter of a rectangle: 2(l+w)

2(2w-4+w)=40

2(3w-4)=40

6w-8=40

6w=40+8

6w=48

w=48/6

w=8

Therefore the width=8;

length= 2w-4 = 2(8)-4 = 16-4 = 12

perimeter = 40 units