Answer:
Step-by-step explanation:
It's a right angle triangle. Use c^2 = a^2 + b^2
a = 12
b = ?
c = 13
12^2 + b^2 = 13^2
144 + b^2 = 169
b^2 = 169 - 144
b^2 = 25
sqrt(b^2) = sqrt(25)
b = 5
