Find the angles of an isosceles triangle if the angle at the base is 47.

An isosceles triangle is a triangle in which the sides are equal, as well as the angles at the base are equal:

AB = BC;

∠А = ∠С = 47º.

Since the sum of all the angles of the triangle is 180º:

∠А + ∠В + ∠С = 180º;

∠В = 180º – ∠А – ∠С;

∠В = 180º – 47º – 47º = 86º.

Answer: angles ∠А and ∠С are equal to 47º, angle ∠В is equal to 86º.