?

ACT® Math

Free Version

Upgrade subject to access all content

Moderate

Isosceles Triangle

ACTMAT-JE13KE

$ \Delta $ABC is an isosceles triangle with vertex A and $AB = AC.$

If the measure of $ {\angle A} $ is $\frac{1}{4}$ the measure of $ {\angle B} $, what is the measure, in degrees, of $ {\angle A} $?

A

$20°$

B

$30°$

C

$45°$

D

$60°$

E

$80°$