Question

If two straight lines intersect then

• A. Sum of adjacent angles is ${180}^{\circ }$
• B. Vertically opposite angles are not equal
• C. Vertically opposite angles are equal
• D. Sum of adjacent angle is ${90}^{\circ }$

Answer 1

Answer: (A), (C)

The correct options are
A

Sum of adjacent angles is ${180}^{\circ }$

C

Vertically opposite angles are equal

If two lines intersect, we observe that adjacent angles

$\angle AOC+\angle AOD=180-x^{\circ }+x^{\circ }$

$\angle AOC+\angle AOD={180}^{\circ }$

and vertically opposite angles are equal.