A right triangle has one angle equal to 90 degrees. A right triangle can also be an isosceles triangle–which means that it has two sides that are equal. A right isosceles triangle has a 90-degree angle and two 45-degree angles. This is the only right triangle that is an isosceles triangle.

What must a right triangle have?

Properties of Right Triangles A right triangle must have one interior angle of exactly 90° . It can be scalene or isosceles but never equilateral.

Do right triangles have equal sides?

Yes, a right triangle can have two equal sides. The longest side is called the hypotenuse and the other two sides may or may not be equal to each other. A right triangle that has two equal sides is called an isosceles right triangle.