Quick answer
A right triangle is a triangle with one right angle of 90°.
- Main formula
- a² + b² = c².
- Quick example
- The perimeter is found by adding the three sides.
How to identify it
Look at the side lengths and angle measures. A clear sketch usually makes the classification immediate.
Main formula
a² + b² = c².
Practice tip
When a height is not shown, draw it perpendicular to the base before calculating area.