SOLUTION: Find the general equation of parabola axis parallel to x-axis and passing through (-1,3/2), (1,0), and (-3,-1) kinda confused in what equation should I use in this problem

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Question 1050215: Find the general equation of parabola axis parallel to x-axis and passing through (-1,3/2), (1,0), and (-3,-1)
kinda confused in what equation should I use in this problem
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
You might have a choice of starting with standard form or with general form. Maybe general form is more comfortable to work with. The parabola is given as axis of symmetry parallel to the x-axis, so instead of y as a function of x, you would want to use x as a function of y:

THIS form: x=ay%5E2%2Bby%2Bc
and the actual UNKNOWNS are the coefficients and constant, a, b, and c.
Setup the three more specific equations using each of the given three points of your parabola.



Simplify the system.

system%28%289%2F4%29a%2B%283%2F2%29b%2Bc=-1%2Cc=1%2Ca-b%2Bc=-3%29
which should be fairly easy to deal with now. Make the OBVIOUS substitution for c.

You should do that and do the rest, having made the system into two equations in the two unknowns of a and b.