In an isosceles triangle, the angle at the base is 70 °. what are the other angles equal to?

A triangle has three points not lying on one straight line, connected by segments.

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

∠А = ∠С.

In this way:

∠А = ∠С = 70º.

Since in any form of triangles the sum of all angles is equal to 180º:

∠А + ∠В + ∠С = 180º;

∠В = 180º – ∠А – ∠С;

∠В = 180º – 70º – 70º = 40º.

Answer: angles ∠А and ∠С are equal to 70º, angle ∠В is equal to 40º.