Question

Which statement is a valid proof involving isosceles triangles?

a) Sides of an isosceles triangle are equal.
b) The base angles of an isosceles triangle are congruent.
c) The sum of the angles in an isosceles triangle is 180 degrees.
d) The hypotenuse of a right isosceles triangle is twice the length of one leg.

Answer 1

The base angles of an isosceles triangle are congruent.

Step-by-step explanation:

The statement that is a valid proof involving isosceles triangles is b) The base angles of an isosceles triangle are congruent. An isosceles triangle is defined as a triangle that has at least two sides of equal length. One of the properties of isosceles triangles is that the base angles (the angles opposite the equal sides) are congruent, which means they have the same measure. This can be proven by using the fact that the sum of the angles in a triangle is 180 degrees and the properties of isosceles triangles.