Question

One of the angles of a triangle is $70°$. If the other two angles are equal, then measure of each of the equal angle is$\_\_\_\_\_$

Answer 1

Given

One angle of a triangle is $70°$

Let the measure of the other two equal angles be $x$

The sum of the angles of a triangle is $180°$

$$\begin{gathered} \therefore x+x+70=180 \\ \Rightarrow 2x+70=180 \\ \Rightarrow 2x=180-70 \\ \Rightarrow 2x=110 \\ \Rightarrow x=\frac{110}{2} \\ \Rightarrow x=55° \end{gathered}$$

Hence, the measure of the other two equal angles is $55°$.