Question

Question 120

In a right-angled triangle, if an angle measures ${35}^{\circ }$, then find the measure of the third angle.

Answer 1

In a right angled $\Delta ABC$,
$\angle A+\angle B+\angle C={180}^{\circ }$ [angle sum property of a triangle]
$\Rightarrow \angle A+{90}^{\circ }+{35}^{\circ }={180}^{\circ }$ $[\because \angle B={90}^{\circ }and\angle C={35}^{\circ },given]$
$\Rightarrow \angle A+{125}^{\circ }={180}^{\circ }\Rightarrow \angle A={180}^{\circ }-{125}^{\circ }={55}^{\circ }$