Hello,

that was a real near miss. You wrote:

Then I divided each side by 4: x^2=81

Then I took the square root of each side: x=9.

The correct answer is: | x | = 9 that means: x = 9 or x = -9.

Now plug in these values into one of the equations. I take the first one (it's easier to calculate):

x = 9: y = 2*(9)^2 = 162

x = -9: y = 2*(-9)^2 = 162

You have two points: (9, 162), (-9, 162)