Question 20

waecmaths question: 

In the diagram XY is a straight line, $\angle POX=\angle POQ$ and $\angle ROY=\angle QOR$ . Find the value of $\angle POQ+\angle ROY$

 

 

Option A: 

60o

Option B: 

90o

Option C: 

100o

Option D: 

120o

waecmaths solution: 

$\begin{align}  & \angle POX=\angle POQ=x \\ & \angle ROY=\angle QOY=y \\ & \therefore \angle POX+\angle POQ+\angle ROY+\angle QOY={{180}^{\circ }}\text{    }\!\!\{\!\!\text{  sum of }\angle \text{s on a straight line }\!\!\}\!\!\text{ } \\ & x+x+y+y={{180}^{\circ }} \\ & 2x+2y={{180}^{\circ }} \\ & x+y={{90}^{\circ }} \\ & \angle POQ+\angle ROY={{90}^{\circ }} \\\end{align}$ 

maths year: