SOLUTION: Which quadratic function is best represented by the graph?https://static.k12.com/nextgen_media/assets/1512578-IM3_140718_060106.jpg

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Question 1191806: Which quadratic function is best represented by the graph?https://static.k12.com/nextgen_media/assets/1512578-IM3_140718_060106.jpg
Found 2 solutions by josgarithmetic, MathLover1:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
The graph of the parabola shows roots 2 and 4; and vertex is at (3,-1). You know two things from that.

(1)
y=a%28x-2%29%28x-4%29
AND
(2)
y=a%28x-3%29%5E2-1
.
.
.

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
as you can see that is a parabola opening up, has vertex at (3,-1)
=>h=3 and k=-1
so, vertex form equation is
y-k=a%28x-h%29%5E2.......substitute h=3 and k=-1
y-%28-1%29=a%28x-3%29%5E2
y%2B1=a%28x-3%29%5E2
y=a%28x-3%29%5E2-1
you also see from the graph that parabola passes through the point (2,0), so use it to calculate a
0=a%282-3%29%5E2-1
0=a%28-1%29%5E2-1
a=1
and your equation is:

y=%28x-3%29%5E2-1

+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+%28x-3%29%5E2-1%29+