Question

The length of a rectangle is three centimeters more than twice the width. The perimeter is 78 centimeters. Define a variable and write and solve an equation to find out how long and wide the rectangle is?

I need to find the length? how?

Answer 1

L = 2w + 3
The perimeter equation is:
2L + 2W = 78
Put what L equals in to find w:
2(2w + 3) + 2w = 78
6w + 6 = 78 ( I did a short cut)
6w = 72
6w/6 = 72/6
W = 12
At this point, put width back into the first equation to find the length
L = 2(12) + 3
L = 27