Answer:
x = 4 sqrt(5)
Explanation:
Since this is a right triangle, we can use the Pythagorean theorem
a^2 + b^2 = c^2 where a and b are the legs and c is the hypotenuse
8^2 + x^2 = 12^2
64+ x^2 =144
Subtract 64 from each side
x^2 = 144-64
x^2 =80
Take the square root of each side
sqrt(x^2) = sqrt(80)
x = sqrt(16*5)
x = 4 sqrt(5)