What are the important points needed to graph y=3x2+6x+1?

1 Answer
Edric Y.
Nov 5, 2015

The vertex: (−1,−2)
The y-intercept: (0,1)
The y-intercept reflected over axis of symmetry: (−2,1)

Explanation:

−b2a=−62⋅3=−1 This is the x-coordinate of the vertex.
y=3(−1)2+6(−1)+1=−2 This is the y-coordinate of the vertex.

The vertex: (−1,−2)

Now plug in 0 for x:
y=3(0)2+6(0)+1=1

The y-intercept: (0,1)

Now reflect that point over the axis of symmetry (x=−1) to get
(−2,1)
to get this, you take −1−(0−(−1))

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