Question

In fig. $△PQR$ right angled at $Q,PQ=6cm$ and $PR=12cm$. Determine $\angle QPR$ and $\angle PRQ$.

Answer 1

Given $PQ=6cm$

$PR=12cm$

$\sin R=\frac{PQ}{PR}$

$=\frac{6}{12}=\frac{1}{2}$

$\sin R=\sin {30}^o$

$R={30}^o$

$\angle PRQ={30}^o$

As $\angle P+\angle Q+\angle R={180}^o$

$\angle P+{90}^o+{30}^o={180}^o$

$\angle P={180}^o-{120}^o$

$\angle P={60}^o$

$\angle QPR={60}^o$ & $\angle PRQ={30}^o$