Quick answer
A isosceles triangle is a triangle with two equal sides and two equal base angles.
- Main formula
- Area = (base x height)/2.
- 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
Area = (base x height)/2.
Practice tip
When a height is not shown, draw it perpendicular to the base before calculating area.