Question

Three angles of a quadrilateral are equal. The fourth angle measure ${120}^{\circ }$. What is the measure of each of the equal angles?

Answer 1

It is given that three angles are equal and measure of fourth angle is ${120}^o.$

Let the measure of each of the equal angles be $x$

We know that, sum of four measure of angles of quadrilateral is ${360}^o.$

$\Rightarrow$ $x+x+x+{120}^o={360}^o$

$\Rightarrow$ $3x+{120}^o={360}^o$

$\Rightarrow$ $3x={240}^o$

$\Rightarrow$ $x={80}^o$

Hence, this is the answer.