Answer: 9 units
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Step-by-step explanation:
For any parallelogram, the opposite sides are parallel and are the same length.
AB = CD
9x+2 = 12x-4
2+4 = 12x-9x
6 = 3x
x = 6/3
x = 2
Which leads to
- AB = 9x+2 = 9(2)+2 = 20
- CD = 12x-4 = 12(2)-4 = 20
- BC = x+7 = 2+7 = 9
Side AD is opposite BC, so AD = BC = 9