S2 Ch9

Referring to the figure, which of the following must true?

I. a = d

II. b + c = 180°

III. c = e

• I only

• I and II only

• II and III only

• I, II and III

In the figure, ABCD is a parallelogram and ABE is a straight line. Which of the following may be false?

• a + b = 180°

• a + d = 180°

• x + d = 180°

• b + d = 180°

In the figure, AOE is a straight line. ∠AOB = ∠COD and ∠BOC = ∠DOE. Find ∠BOD.

• 60°

• 90°

• 120°

• Cannot be determined

Referring to the figure, which of the following must be true?

I. x = b

II. x + y = a + b

III. x + y + a + b = 360°

• I only

• II only

• III only

• I and III only

In the figure, ABDF and CDE are straight lines. Which of the following must be true?

• x = y

• x = y − z

• x = y + z

• x + y − z = 180°

Referring to the figure, which of the following must be true?

I. a + b + c = 180°

II. a + b + c = 360°

III. a = c

• I only

• II only

• III only

• None of above

In the figure, a + b + c + d =

• x − 180°.

• 180° − x.

• 90° + x.

• 360° − x.