Answer:
12.1
Step-by-step explanation:
c^2 - b^2 = a^2 (how to find one side using the hypotenuse and another side)
14^2 - 7^2 = a^2 (plug in c and b)
196 - 49 = a^2 (simplify exponents)
147 = a^2 (subtract)
a ≈ 12.1 (square root 147 and round to nearest tenth)