Answer:
√41 or 6.40
Step-by-step explanation:
Pythagorean theorem:
a² + b² = c²
The third side is considered the hypotenuse (c²).
a² and b² will be represented by the legs.
a² = 4²
b² = 5²
c² = c²
4² + 5² = c²
16 + 25 = c²
31 = c²
√41 = c
[tex]\displaystyle\bf\\\textbf{A third side is hypotenuse.}\\\\The~length~of~the~hypotenuse=\sqrt{cat1^2+cat2^2}~~~(T.Pithagoras)\\\\The~length~of~the~hypotenuse=\sqrt{4^2+5^2}=\sqrt{16+25}=\boxed{\bf\sqrt{41}}[/tex]
