it's a right angled triangle so we will use hypotenuse formula to get the value of x
hypotenuse formula = a² + b² = c²
a = side of the triangle
b = base of traingle
c = hypotenuse ( can be written as h too)
and the formula can also be written as.
c² = a² + b²
therefore, x = 12.1
hope this answer helps you dear...take care!