Question

the measure of the vertex angle of an isosceles triangle is 70. find the measure of a base angle of the triangle.

Explanation:

Step1: Sum of triangle angles

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

Step2: Subtract vertex angle

Subtract the vertex angle from the total:
$180^\circ - 70^\circ = 110^\circ$

Step3: Divide by 2 for base angles

Base angles are equal; divide the result by 2:
$\frac{110^\circ}{2} = 55^\circ$

Answer:

$55^\circ$