The ratio of the measure of the vertex angle
to the base angle of an isosceles triangle is
8:5. Find the measure of the vertex angle.

Respuesta :

Answer:

the vertex angle = 80°

Step-by-step explanation:

V: vertex angle     B: base angle

V / B = 8 / 5

5V = 8B

V + 2B = 180

4V + 8B = 720

4V + 5V = 720

9V = 720

V = 80°

check: B = (180 - 80) / 2 = 50°

V / B = 80 / 50 = 8 /5   (8 : 5)