To find the zeros, set y = 0 \(-5(x-4)^2 +10 = 0\) Now try to isolate the (x-4)^2 term (move 10 to right side, divide by -5) \((x-4)^2 = \frac{-10}{-5} = 2\) Next take square root of both sides (this cancels the square on (x-4)) \(x-4 = \pm \sqrt{2}\) \(x = 4 \pm \sqrt{2}\)
For interpretation, x = price, y = profit We are solving for price where profit = 0.