Answer:
c is 13.
Explanation:
What we know:
Side a is 5 cm long.
Side b is 12 cm long.
What we need to know: What is c?
What do we do?:
a² + b² = c²
Substitute a and b for 5 and 12.
5² + 12² = c²
Find the squares of 5 and 12, which are 25 and 144.
25 + 144 = c²
Add 25 and 144 to get 169.
169 = c²
Find the square root of 169, to get c. That would be 13.
√169 = c
13 = c
Thus, side c is 13 cm long.