Answer:
D
Step-by-step explanation:
Using Pythagoras' identity in the right triangle
The square oh the hypotenuse is equal to the sum of the squares on the other 2 sides, that is
h² = (9[tex]\sqrt{2}[/tex] )² + (9[tex]\sqrt{2}[/tex] )² = 162 + 162 = 324 ( take the square root of both sides )
h = [tex]\sqrt{324}[/tex] = 18 → D
