How do you graph and identify the vertex and axis of symmetry for #y=2(x+1)^2-4#?

1 Answer
Jun 7, 2017

There are some formulas, sorry for vague summary

Explanation:

To graph the equation, you can plug in 5 x-values, plot the points, and draw the rest of the graph from there. It usually takes 5 points to draw a parabola. 5 good x-values are the vertex and two points equally spaced on either side..

This equation is in the accurately named vertex form, so it is fairly easy to find the vertex. The form of the equation is:

#y = a(x-h)^2+k#

In this case:

a = 2
h = -1 (the formula is minus h, so +1 is really -1.)
k = -4

In vertex form, the vertex is (h,k).

So I think you can find that on your own :)

The axis of symmetry is a vertical line in the center of a parabola. Since it is in the center, it runs through the vertex. Which means that the line's x-value is the same as the x-value of the vertex.

So pretty much draw a vertical line through the vertex.