What is the length of the unknown leg to the nearest tenth?
A) 12.5
B 18.9
C) 2.4
D) 5.1

Answer:
A
Step-by-step explanation:
a^2 + b^2 = c^2
a^2 + 100 = 256
a^2 = 156
a = 12.48
a = 12.5