The triangle with edge lengths 3, 4, and 5 is the right triangle with smallest possible integer lengths and corresponds to the Pythagorean triple where the legs have lengths 3 and 4 and the hypotenuse length 5. It satisfies the Pythagorean theorem since
The formula for the area of a triangle is 1/2 x base x height
The formula for finding the hypotenuse is a² + b² = c²