Question

the measure of the vertex angle of an isosceles triangle is 50. find the measure of a base angle of the triangle.

Explanation:

Step1: Recall triangle angle sum

The sum of angles in a triangle is $180^\circ$.

Step2: Subtract vertex angle

Subtract the given vertex angle from $180^\circ$.
$180^\circ - 50^\circ = 130^\circ$

Step3: Divide by 2 for base angles

Isosceles base angles are equal, so divide by 2.
$\frac{130^\circ}{2} = 65^\circ$

Answer:

$65^\circ$