Question
Find angle $ 'A\ '$ if :
✓
Answer
From the figure we have
$\cos A=\frac{10}{20}$
$ \cos A=\frac{1}{2}$
$ \cos A=\cos 60^{\circ} $
$ A=60^{\circ}$
$\cos A=\frac{10}{20}$
$ \cos A=\frac{1}{2}$
$ \cos A=\cos 60^{\circ} $
$ A=60^{\circ}$
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