Let a = 5 cm, b = 12 cm, and c
= ? Using Pythagorean theorem

c is 13.

Step-by-step 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.