Answer:
A. x = 5
Step-by-step explanation:
This triangle is a right triangle, so we can use the Pythagorean theorem.
a^2 + b^2 = c^2
3^2 + 4^2 = x^2
9 + 16 = x^2
25 = x^2
x^2 = 25
x = sqrt(25)
x = 5
