Answer:
w = 9, l = 12
Explanation:
If w is the width and l is the length, then:
l = 2w − 6
The area of the rectangle is width times length.
A = wl
Substituting and solving:
108 = w (2w − 6)
108 = 2w² − 6w
54 = w² − 3w
0 = w² − 3w − 54
0 = (w + 6) (w − 9)
w = -6 or 9
The width is 9, so the length is 12.