- Measure of angle C = 100°
- Measure of angle A = 40°
- We know, sum of all angles of a triangle is 180°.
- Therefore, the measure of angle B
= [180 - (100 + 40)]° = 40°
- When two angles of a triangle are equal, then the triangle is isosceles.
- Here, the measure of angle A and B are equal, i.e., 40°
- So, ∆ABC is an isosceles triangle.
Answers:
- 40°
- Yes
Hope you could get an idea from here.
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