Determinig the c value from a quadratic equation

So i have http://webwork.mathstat.concordia.ca...2f91f155d1.png has vertex http://webwork.mathstat.concordia.ca...72288ecee1.png.

i figured out b as 24 now i need to find c

I guess I can just do 7=-6x^2+24x+c and the solve for C and my x's should be 2

Re: Determinig the c value from a quadratic equation

Once you have solved for b, and put it into the equation like you have, inputting the vertex for the values x and y and solving for C, would give you the answer for c. You are correct.

Re: Determinig the c value from a quadratic equation

yes pretty much. Taking the derivative once and then finding b. And once you found b you can find c.