We recognize this as a parabola that opens at the bottom. It is a parabola because the highest exponent is the square. It opens at the bottom because the x2 term has a negative coefficient.
So the x coordinate of the vertex is (-b / 2a) where a is -0.75 and b is 18
-b/ 2a = - (18) / 2 ( -0.75) = -18/ -1.5 which is 12. That is the amount the tickets must sell for.
To find the maximum intake, put 12 into the equation in place of p and evaluate.
Asra R.
This helped a lot! Tysm!!10/11/23