Answer:
y = 2 ( x − 1 ) ^ 2 + 2
Step-by-step explanation:
y = a ( x − h ) ^ 2 + k
where vertex is (h,k) = (1,2)
h=1, k=2
y = a ( x − 1 ) ^ 2 + 2
sub ( 3,10)
10 = a (3 - 1)^2 + 2
a=2
y = 2 ( x − 1 ) ^ 2 + 2
Answer:
Step-by-step explanation:the anwser is the middle one
The easiest way is to try the point (-4,1), that is, x=-4, y=1,
to see which equation works.
b works.
The usual way to do it is to find the equation of the circle
standard form of a circle is (x-h)²+(y-k)²=r², (h,k) are the coordinates of the center, r is the radius.
in this case, the center is (-2,1), so (x+2)²+(y-1)²=r²
the given point (-4,1) is for you to find r: (-4+2)²+(1-1)²=r², r=2
so the equation is (x+2)²+(y-1)²=2²
expand it: x²+4x+4+y²-2y+1=4
x²+y²+4x-2y+1=0, which is answer b.
