Question

In the figure a pair of parallel lines are cut by a transversal. Find the value of a and b respectively.

• A. ${72}^{\circ },{72}^{\circ }$
• B. ${72}^{\circ },{47}^{\circ }$
• C. ${62}^{\circ },{62}^{\circ }$
• D. ${57}^{\circ },{62}^{\circ }$

Answer 1

The correct option is A

${72}^{\circ },{72}^{\circ }$

$\angle a={72}^{\circ }$
(Alternate interior angles are equal)

$\angle a=\angle b$
(Vertically opposite angles are equal)

$\Rightarrow \angle b={72}^{\circ }$