The hypotenuse of a right triangle is 25 cm, and the shorter leg is 15 cm. What is the length of the other leg?

Apr 3, 2018

The other leg is $\text{20 cm}$.

Explanation:

So the equation for the Pythagorean theorem is

${a}^{2} + {b}^{2} = {c}^{2}$

The hypotenuse is always the $c$. It does matter if $25$ is plugged into $a$ or $b$. So

${15}^{2} = 225$ and ${c}^{2} = {25}^{2} = 625$

So

Subtract $225$ from both sides. You have ${a}^{2}$ (or ${b}^{2}$) $= 400$. Square root on both sides. Therefore, ${a}^{2}$ (or ${b}^{2}$), i.e. the other leg, is $\text{20 cm}$.