The base angle of an isosceles triangle is 15 less than three times the vertex angle. What is the vertex angle?

A triangle has the following side lengths:

Which of the following correctly describes the triangle?

The base angle of an isosceles triangle is 15 less than three times the vertex angle. What is the vertex angle?

A triangle has the following side lengths:

Which of the following correctly describes the triangle?

The base angle of an isosceles triangle is five more than twice the vertex angle. What is the base angle?

The base angle of an isosceles triangle is five more than twice the vertex angle. What is the base angle?

An isosceles triangle has an area of 12. If the ratio of the base to the height is 3:2, what is the length of the two equal sides?

An isosceles triangle has an area of 12. If the ratio of the base to the height is 3:2, what is the length of the two equal sides?

Two sides of an isosceles triangle are 20 and 30. What is the difference of the largest and the smallest possible perimeters?

Two sides of an isosceles triangle are 20 and 30. What is the difference of the largest and the smallest possible perimeters?