A right-angle triangle is also commonly referred to as a right-angled triangle or a right triangle. In mathematical terms, it is a triangle with one angle measuring 90 degrees. Another synonym for this type of triangle is a rectangular triangle. This is because the right angle creates a square or rectangle within the triangle. Additionally, it can be called a Pythagorean triangle, as the Pythagorean theorem is often applied to calculate its sides and angles. Furthermore, it is sometimes referred to as a 3-4-5 triangle, as a triangle with sides of 3, 4, and 5 units is always a right-angled triangle.