Hello!
We have a quadratic equation:
[tex]P(x)=6x^2-60x+126[/tex]As the coefficient a is positive, the concavity of the parabola will face upwards (so it will have a minimum point).
Look at the graph below:
Now, let's analyze the graph and the alternatives:
• when x = 5, profit is as small as possible
when x = 4 or x = 6, the profit