Question

If AOB is a straight line, then $x^{\circ }+y^{\circ }$=___________.

• A. ${180}^{\circ }$
• B. ${360}^{\circ }$
• C. ${18}^{\circ }$
• D. None of the above

Answer 1

The correct option is A ${180}^{\circ }$

A Linear pair is a pair of adjacent angles where the non-common side forms a straight line. Angles in a linear pair are supplementary, i.e. they add upto ${180}^{\circ }$.
Hence $x^{\circ }+y^{\circ }={180}^{\circ }$.