In a Right Triangle, Find the Length of the Side $\mathrm{b}=20 \mathrm{~cm}, \mathrm{c}=25 \mathrm{~cm}$

Multiple Choice

In a right triangle, find the length of the side not given. Let c represent the length of the hypotenuse. Give an answer to the nearest tenth if necessary.
- $\mathrm{b}=20 \mathrm{~cm}, \mathrm{c}=25 \mathrm{~cm}$

A) $\mathrm{a}=15 \mathrm{~cm}$
B) $a=5 \mathrm{~cm}$
C) $a=45 \mathrm{~cm}$
D) $a=225 \mathrm{~cm}$