What is the vertex of #y= 2x^2 + 8x − 3#?

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Answer 1 · 2018-05-08T00:42:43

You can find the line of symmetry, and then plug in to find the #y# point that correlates to this line.

To do this, use

#-b/(2a)#

to give you the line of symmetry. So

#-8/(2 * 2)=-2#

Now, you can plug this back into the original so you will receive

#y=2(-2)^2+8(-2)-3#

This comes out to a value of

#y = 8 - 16 - 3#

#y=-11#

So the vertex will be #(-2,-11)#.

graph{2x^2 + 8x -3 [-5, 5, -15, 5]}