Answer:
10
Explanation:
This is a right triangle, so we can use the Pythagorean theorem
a^2+b^2 = c^2 where a and b are the legs and c is the hypotenuse
9^2 + (sqrt(19))^2=c^2
81+19 = c^2
100 = c^2
Take the square root of each side
sqrt(100) = sqrt(c^2)
10 = c
The hypotenuse is 10