Question

In the given figure, $\angle$POR and $\angle$QOR form a linear pair and $a-b={40}^o$. Then the values of a, b respectively are __________.

• A. ${110}^o,{70}^o$
• B. ${70}^o,{100}^o$
• C. ${80}^o,{120}^o$
• D. ${120}^o,{80}^o$

Answer 1

Answer: (A)

${110}^o,{70}^o$

$\angle POR$ $=b$ and$\angle QOR$ $=a$

$\because$ line PQ is a straight line

$\Rightarrow$ $\angle POQ$ $=$ ${180}^{\circ }$

$\Rightarrow$ $a+b$ $={180}^{\circ }$ $....\left(1\right)$

$\because$ $a-b$ $={40}^{\circ }$ $....\left(2\right)$

From equation (1) and (2)

$a$ $={110}^{\circ }$ and $b$ $={70}^{\circ }$

Hence the correct option is $\left(A\right)$ ${110}^{\circ }$$,{70}^{\circ }$