Question

1. In a
triangle ABC, if angle A =55° and angle B =40°, find angle C.
​

Answer 1

Answer: 85°

Step-by-step explanation:

In ∆ABC,

We know that sum of all the angles of a triangle is 180°

Therefore,

Angle A + Angle B + Angle C = 180°

55° + 40° + Angle C = 180°

Angle C = 180° - 95°

Therefore, Angle C = 85°

Answer 2

Answér :

∠C = 85°

Note :

★ Angle sum property of a triangle :

The sum of all the interior angles of a triangle is 180° .

Solution :

• Given : In ∆ABC, ∠A = 55° & ∠B = 40°
• To find : ∠C = ?

We know that ,

According to the angle sum property of a triangle , the sum of all the three interior angles of a triangle is 180° .

Thus ,

In the given∆ABC ,

=> ∠A + ∠B + ∠C = 180°

=> 55° + 40° + ∠C = 180°

=> 95° + ∠C = 180°

=> ∠C = 180° - 95°

=> ∠C = 85°

Hence ,

Required answer is 85° .