Question

In a triangle ABC if AB= AC and angle B=65° find angle C and angle A

Answer 1

angle C will be 65° as opp. angle of equal side are equal.
and by angle some property.
A + B + C = 180°
2× 65° + A = 180°
A = 180° - 130
A = 50°

Answer 2

Given:

• AB = AC
• ∠B = 65°

To Find:

• The value of ∠C and ∠A.

Solution:

We can say that the triangle ABC is an isosceles triangle as AB = BC.

This implies ∠C = ∠B {AB= BC}

The value of ∠B = 65° {given}

∴ ∠C = 65°

∠A+∠B+∠C = 180° {Sum of all the angles of trianhle = 180°}

On substiting the values of ∠B and ∠C in the above equation we get,

⇒ ∠A + 65° + 65° = 180° {adding the terms in LHS}

⇒ ∠A + 130° = 180°

⇒ ∠A = 180°-130° {subtrcating the terms}

⇒ ∠A = 50°

∴ The value of ∠C and ∠A is 65° and 50° respectively.