## Least Side Length of Right Triangle

If the lengths of two sides of a right triangle are $3$ and $4$, what is the least possible length of the third side?
Source: NCTM Mathematics Teacher, October 2006

Solution
If the legs of the right triangle measure $3$ and $4$ units, then the hypotenuse measures $5$ units. If one leg measures $3$ and the hypotenuse measures $4$, then the other leg measures
$\sqrt{4^2-3^2}=\sqrt{7}<5$

Answer: $\sqrt{7}$ units