# The angle at the base of an isosceles triangle is 45 (degrees) 25. Find the angle at the vertex.

From the condition we know that the angle at the base of an isosceles triangle is 45 °. In order to find the angle at the vertex, we will use the property of angles at the base of an isosceles triangle and the theorem on the sum of the angles of a triangle.

So, the angles at the base of an isosceles triangle are equal to each other.

And the theorem on the sum of the angles of a triangle says that the sum of the angles of a triangle is 180 °.

So, in order to find the angle at the apex of the triangle, we will subtract the sum of the angles at the base from 180 °.

180 ° – (45 ° + 45 °) = 180 ° – 90 ° = 90 ° angle at the apex of an isosceles triangle. One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.