Question

ABC is a triangle in which AB = AC. The base BC is produced to D and angle 130°. Then what is the value of angle A?​

Answer 1

Use the riot formula

It says the measure of the exterior angle is equal to the sum of remote interior angles

Answer 2

Answer:

80

Step-by-step explanation:

ANGLE  (A+B+C)=180----------1

C=B-------2

C+130=180

C=50---------3

A=180-100---------FROM 1,2,3

A=80