Question

The measure of $\angle A$ in the given triangle (in degrees) is ___.


$\left[1\right]$

Answer 1

In the given triangle,
$A{B}^2=8^2=64,A{C}^2={15}^2=225,andB{C}^2={17}^2=289.$

Since $B{C}^2=A{C}^2+A{B}^2,$ $△ABC$ is a triangle which is right-angled at A.

$\Rightarrow \angle A={90}^{\circ }$
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