In $\triangle$ $PQR,$ right-angled at $Q$ (see $Fig.$), $PQ =3 \,cm$ and $PR =6 \,cm$. Determine $\angle QPR$ and $\angle PRQ$.
In $\triangle$ $PQR,$ right-angled at $Q$ (see $Fig.$), $PQ =3 \,cm$ and $PR =6 \,cm$. Determine $\angle QPR$ and $\angle PRQ$.
Given $PQ =3\,cm$ and $PR =6 \,cm$
$\frac{ PQ }{ PR }=\sin R$
$\sin R =\frac{3}{6}=\frac{1}{2}$
$\angle PRQ =30^{\circ}$
$\angle QPR =60^{\circ}$
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