Answer:
Step-by-step explanation:
10). AD = BC [If ABCD is a parallelogram]
3x + 1 = 6x - 4
6x - 3x = 1 + 4
3x = 5
x =
11). If ABCD is a parallelogram,
AB = CD
5x - 8 = 2x + 7
5x - 2x = 7 + 8
3x = 15
x = 5
12). If ABCD is a parallelogram,
AB = CD
AB║CD and BD is a transversal intersecting these parallel lines.
∠ABD ≅ ∠BDC [Alternate interior angles]
4x - 1 = x + 38
4x - x = 38 + 1
3x = 39
x = 13