Question

The measure of two angles of a triangle are $15°$ and $35°$. What is the measure of the third triangle? What type of triangle is this?

Answer 1

According to the angle sum of a triangle, the sum of all the angles of a triangle will always be equal to $180°$.

Let the third angle of the triangle be $x.$

Now, $15°+35°+x=180°$

$$\begin{gathered} 50°+x=180° \\ x=180°-50° \\ x=130° \end{gathered}$$

Hence, the third angle of the triangle is $130°$.

Since, one of the angle of a triangle is obtuse angle, therefore the given triangle is obtuse-angled triangle.