Question

A ray OC is constructed on a line segment AB such that ∠BOC is x°. ∠AOC is ______.

• A. $x^{\circ }$
• B. ${180}^{\circ }-x^{\circ }$
• C. ${90}^{\circ }-x^{\circ }$
• D. ${360}^{\circ }-x^{\circ }$

Answer 1

The correct option is B ${180}^{\circ }-x^{\circ }$

AB is a straight line and the ray OC is drawn on the line segment AB at a point O.​

Therefore,​

∠AOC + ∠BOC = 180° (∠AOC and ∠BOC forms a linear pair)​

∠AOC = 180° - ∠BOC ​

∠AOC = 180° - x°​

​

Answer: (C) 180° - x°