Question

In a parallelogram ABCD, if $\angle D={115}^{\circ }$ then write the measure of $\angle A$

Answer 1

In ||gm ABCD,

$\angle D={115}^{\circ }$

But $\angle A+\angle D={180}^{\circ }$ (Sum of consecutive angles of a ||gm)

$\Rightarrow \angle A+{115}^{\circ }={180}^{\circ }\Rightarrow \angle A={180}^{\circ }-{115}^{\circ }$

$\therefore \angle A={65}^{\circ }$