Question 430209
P(x)=-0.002x^2+1.4x-150
.
Since the coefficient associated with the x^2 term is negative, we know that it is a parabola that opens downwards.  Therefore, the vertex is the maximum.
The value of x of the vertex can be found by:
x = -b/(2a)
x = -1.4/(2*(-0.002))
x = 1.4/0.004
x = 350 pretzels