Question

HELP PLEASE!

Isosceles triangle ABC is shown below.
Triangle A B C. Angles B and C are x. Sides C A and B A extend to form an exterior angle at point A with a measure of 22 degrees.

What is the value of x?
22°
79°
136°
158°

Answer 1

Isosceles add upto 180°

To find x =180°-22°=158°

Answer 2

x = 79°

Explanation:

→ Remember that vertically opposite angles are equal so 22° is opposite to CAB so angle CAB is 22°

CAB = 22°

→ Remember the fact that

• Angles in a triangle add up to 180°
• Base angles in an isosceles triangle are equal

Using the information we form an equation,

2x + 22 = 180

→ Minus 22 from both sides to isolate 2x

2x = 158

→ Divide both sides by 2 to isolate x

x = 79°