Answer:
a
Step-by-step explanation:
it's a right triangle so we can use the pythagorean theorem to find h
pythagorean theorem: a^2+b^2=c^2
h^2+19^2=21^2
h^2+361=441
h^2=80
h≈ 8.9ft
The answer is A: h^2 + 19^2 =21^2 ; 8.9ft
