Question

In triangle ABC angle A=100 and AB=AC find angle Band angle C​

Answer 1

Step-by-step explanation:

Let angle B and Angle C be x°

Sum of angles of triangle = 180°

According to angle sum property of triangle,

Angle ABC + Angle ACB + Angle BAC = 180°

x° + x° + 100° = 180°

2x° + 100° = 180°

2x° = 180° - 100°

2x° = 80°

x = 80/2

x° = 40°

To check:

40° + 40° + 100°

= 180°

Hence, proved.

Answer 2

Answer:

∠B = ∠C = 40°

Step-by-step explanation:

Given that :

In triangle ABC angle A= 100°

∠AB = ∠AC

To Find :

∠B and ∠C​.

Solution :

Given :

AB = AC.

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Angles opposite to equal sides in a triangle are equal.

So,

∠ C = ∠B.

We know that :

Angle sum property of triangle.

So,

⇒ ∠A +∠B + ∠C = 180°

⇒ (∠A) 100 + ∠B + ∠C = 180°

⇒ 2B = 80°

⇒B = 40°

⇒ ∠B = ∠ C = 40°

We know that :

Angles opposite to equal sides in a triangle are equal.

So,

∠ B =40°

∠ C  =40°

Hence, ∠B = ∠C = 40°