Question

Which of the following angles is NOT equal to x $\left(\angle ABC\right)$?
[PR and QS are parallel lines
AD and BC are parallel lines]

• A. b
• B. a
• C. z
• D. y

Answer 1

The correct option is A

b

Considering AB as the transversal for the parallel lines $\stackrel{⟷}{AD}and\stackrel{⟷}{BC}$.

x = a [corresponding angles]

a = z [vertically opposite angles]
Since x = a and a = z, we have x = z.

x = y [vertically opposite angles]

b = ${180}^{\circ }-x$

Hence b is not equal to x.