Question

From given figure, In ∆ABC, AB ⊥ BC, AB = BC then m∠A = ?

Answer 1

AB = BC     ......[Given]

∴ ∠A = ∠C   ......[Isosceles triangle theorem]

Let ∠A = ∠C = x

In ∆ABC,

∠A + ∠B + ∠C = 180°    ...[Sum of the measures of the angles of a triangle is 180°]

∴ x + 90° + x = 180°

∴ 2x = 90°

∴ x = `(90°)/2`

∴ x = 45°

∴ m∠A = 45°