SOLUTION: I have tried completing the square and quad formula for the following question and I am stuck.. y=2xsquared-8 I have to graph this but do not know how?.. Obviously y=-8 but how

Question 350939: I have tried completing the square and quad formula for the following question and I am stuck..
y=2xsquared-8
I have to graph this but do not know how?..
Obviously y=-8 but how do I find x?
Thanks for any input since I seem to be having a brain fart...
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Start with the given equation.

Plug in

Add 8 to both sides.

Divide both sides by 2.

Reduce.

Flip the equation.

Take the square root of both sides.

or Break up the plus/minus.

or Take the square root of 4 to get 2.

So when , or

Put another way, we have the points (2,0) and (-2,0)

So the x-intercepts are (2,0) and (-2,0)

If you need more help, email me at jim_thompson5910@hotmail.com

Also, feel free to check out my tutoring website

Jim
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