by changing $\displaystyle -100x^2-6000x+488000$to f(x) = a(x-h)²+k form ?
Yes, you want to change the equation to that form. Be careful, though. You made a mistake in multiplying it out. The correct equation is $\displaystyle f(x) = -100x^2 + 2000x + 480000$.
Yes, you want to change the equation to that form. Be careful, though. You made a mistake in multiplying it out. The correct equation is $\displaystyle f(x) = -100x^2 + 2000x + 480000$.
how did you get 2000x if you multiply 100x with 80 ?