SOLUTION: find an equation of the parabola which passes through the points (1,3) and (-2, 0)

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Question 877615: find an equation of the parabola which passes through the points (1,3) and (-2, 0)
Found 2 solutions by jim_thompson5910, josgarithmetic:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Unfortunately there isn't enough info since you need at least 3 points to define a parabola.

Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Two points do not define a parabola. Are you hoping for any parabola which will fit? Infinite parabolas may hold any two given points. One of your given points shows a "root", so you could begin by saying, y=%28x%2B2%29%28x-r%29. You have one more given point which you can use by saying, 3=%281%2B2%29%281-r%29, assuming the leading coefficient on x^2 is 1.

Now, with the coordinate values substituted, solve for r.
3%281-r%29=3
3-3r=3
-3r=0
r=0.

Your possible parabola as an equation can be highlight%28y=%28x%2B2%29x%29.
You can have any nonzero value for a for the parabola y=ax%28x%2B2%29 and this will also work with the two given points.