SOLUTION: which way the parabola opens?

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Question 605673: which way the parabola opens?
Answer by mathie123(224) About Me  (Show Source):
You can put this solution on YOUR website!
I have lame ways of remembering some things, this being one of them:
With your equation in the form
ax%5E2%2Bbx%2Bc=0
If the a is negative, then your parabola is making a sad face (opening downwards)
If the a is positive, then your parabola is making a happy face (opening upwards)