Answer:
20.25 m²
Step-by-step explanation:
the area (A) and circumference (C) of a circle are calculated using the formulae
C = 2πr and A = πr² ( where r is the radius )
calculate the radius using the formula for circumference
2πr = 9π ( divide both sides by 2π )
r =
=
= 4.5, hence
A = π × 4.5² = 20.25π m²
The vertex-form equation is
y = a(x+1)² -16
Putting in the y-intercept values, we have
-15 = a(0+1)² -16
1 = a . . . . . . . . . . . add 16
Then the x-intercepts can be found where y=0.
0 = (x+1)² -16
16 = (x+1)²
±4 = x+1
x = -1 ± 4 =
{-5, 3}
I believe the answer is A because the square root of 10 root 3 is approximately 17.32.