Question

If $\angle P$ and $\angle Q$ are complementary in a triangle $PQR,$ then the measure of $\angle R$ is complementary in a triangle $PQR,$ then the measure of $\angle R$ is:

• A. ${45}^0$
• B. ${60}^0$
• C. ${75}^0$
• D. ${90}^0$

Answer 1

The correct option is D ${90}^0$

Complementary angles: Either of two angles whose sum is ${90}^o$ of a triangle.

$\therefore$ As per given data,

$\angle P+\angle Q={90}^o$

But, measure of any triangle sums up to ${180}^o$

$\therefore \angle R=180-90={90}^o$ (property of triangle)