When and how to use the Pythagorean theorem?

Definition:

Pythagorean theorem (also known as Pythagoras' theorem) is a mathematical statement about the relation among the three sides of a right triangle (right-angled triangle).

It states:

"In a right angled triangle, the square of the hypotenuse is equal to the sum of the squares of the other two sides."

In any right-angled triangle, if the sides forming the right-angle are known as a and b and the hypotenuse as c, then the relation among the three sides of a right triangle is given by this equation: a2 + b2 = c2.

When to use it:

If the length of two sides of a right angled triangle are already known, you can find the unknown length of the third side.

How to use it:

As you know the relation among the three sides of a right triangle is represented by the equation a2 + b2 = c2 , substitute the known values in the equation and find out the length of the third side by solving the equation.

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