Find the value of x for which ABCD must be a parallelogram.
Answer options:
5
3
17
34
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Answer:
Opposite sides of the parallelogram are equal :
→ BC = AD
→ 5x - 8 = 2x + 7
→ 5x - 2x = 7 + 8
→ 3x = 15
→ x = 15/3
→ x = 5
Therefore, the value of x is 5.