Answer:
5
Step-by-step explanation:
a²+b²=c² // Plug in 3 and 4 into a and b
3²+4²=c² // Square 3 and 4
9+16=c² // Add 9 and 16
√25=√c² // Square root both sides
5=c
Or just apply the 3-4-5 rule.
