Answer:
x = sqrt(11)
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 sides and c is the hypotenuse
x^2 +(sqrt(5))^2 = 4^2
x^2 +5 = 16
x^2 =16-5
x^2 = 11
Taking the square root of each side
x = sqrt(11)