Question

A ray OC is constructed on the line segment AB such that $\angle BOC$ is $x^{\circ }$.

What will $\angle AOC$ be?

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

Answer 1

The correct option is D

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

AB is a straight line and the ray OC is drawn on the line segment AB. Therefore,

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

($\angle AOC$ and $\angle BOC$ are linear pair of angles)

$\angle AOC={180}^{\circ }-\angle BOC$

$={180}^{\circ }–x^{\circ }$