Please ensure that you've copied down this problem correctly. You speak of someone named "Yarin" but also speak of "my" and "I". Are there really two different people who "star" in this problem? Are you studying "ratios" right now?
When you round that number you get 7,000
Your answer for Q is rotated over the period and flipped upside down.
The complete question in the attached figure
we know that
the equation of a parabola is
y=a(x-h)²+k
where
(h,k) is the vertex --------> (h,k)--------> (-1,2)
so
y=a(x+1)²+2
point (2,20)
for x=2
y=20
20=a(2+1)²+2--------> 20=a*9+2--------> 9*a=18---------> a=2
the equation of a parabola is
y=a(x+1)²+2-------> y=2(x+1)²+2
therefore
the answer is the option
<span>
C) f(x) = 2(x + 1)2 + 2</span>