In a cyclic quadrilateral $ABCD$, if $m \angle A = 3(m \angle C)$. Find $m \angle A$.
Given:
In a cyclic quadrilateral $ABCD$, $m \angle A = 3(m \angle C)$.
To do:
We have to find $m \angle A$.
Solution:
$ABCD$ is a cyclic quadrilateral.
$\angle A + \angle C = 180^o$
$3 \angle C + \angle C = 180^o$
$4\angle C = 180^o$
$\angle C = \frac{180^o}{4}$
$ = 45^o$
This implies,
$\angle A = 3 \times 45^o= 135^o$
Hence, $m \angle A =135^o$.
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