In ΔABC, AB = AC. If ∠A is twice the sum of other two angles of the triangles, then the measure of $\frac{1}{2}$ ∠A is :
Answer & explanation
Correct answer: option 2
If the two sides of a triangle is equal then it will be a isoceles triangle.
We have,
In ΔABC, AB = AC. If ∠A is twice the sum of other two angles.
So, the sum of angles of a triangle = 180o
Let the value of ∠A = 2x
then the value of other two angles will be = x
So, 2x + x = 180
x = 60
and ∠A = 12x = 120o
So, the value of $\frac{1}{2}$ × ∠A = $\frac{1}{2}$ × 120 = 60o