quadratic function question

[ian goh]

hello attached is my attempt on finding a and b value of quadratic, but im not sure how to get the answer. Thank you for any help!

 

[BigBeachBanana]

hello attached is my attempt on finding a and b value of quadratic, but im not sure how to get the answer. Thank you for any help!

Since you know the roots of the quadratic and are given c=-12, you can solve for a and b using the quadratic formula. The problem reduces to a system of 2 equations and two unknowns a and b.
$$x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}$$

 

[Steven G]

Your work is perfect. You just need to continue!

You have that y=a(x+2)(x-3).

Now use the point (0, -12) to find a.

Once you have a, just multiply out a(x+2)(x-3) and you'll be done.

I would have done the problem just as you did.

Finish up and show us your result.