Question

QRST is a parallelogram. Find b.

Answer 1

Because QRST is a parallelogram,

QR = TS, or

b+11=2b, so

b=11.

Answer 2

Parallelogram ⇒ Opposite sides are equal

b + 11 = 2b

.

Solve b:

b + 11 = 2b

2b - b = 11

b = 11

.

Answer: b = 11