I need help with finding the a and q values if the defining equation f is f(x)= ax^2 + q

with the x and y values being (-3;6) and (3;6)

x y x y

How would u go about solving this equation :)

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- May 3rd 2010, 09:56 AMMixxie16Parabola: finding the a and q values
I need help with finding the a and q values if the defining equation f is f(x)= ax^2 + q

with the x and y values being (-3;6) and (3;6)

x y x y

How would u go about solving this equation :) - May 3rd 2010, 11:25 AMshenanigans87
- May 3rd 2010, 01:22 PMArchie Meade
Hi Mixxie,

if a=1, then q=-3

You need 2 clues to find "a" and "q".

The two pieces of information you are given are unfortunately

not giving two simultaneous equations as they are both

$\displaystyle 9a+q=6$

since $\displaystyle (-3)^2=3^2$

The graph of the function is parabolic, the axis of symmetry is the y-axis.

$\displaystyle f(0)=q$

There are an infinite number of solutions until another clue is given.

$\displaystyle a=2,\ 2(9)+q=6,\ q=-12$

$\displaystyle a=3,\ 3(9)+q=6,\ q=-21$

etc