1) Considering that x is for pounds of apples and y is a total cost of an apple let's find the cost per pound of the apples, given that the y=2.57x +4.5
Let's turn that function into an equation
0=2.57x +4.5 Subtract 2.57x from both sides
-2.57x=4.5 Divide both sides by -2.57
x=-1.75
2) So if no one pie crust is sold, there is going to be a loss of $-1.75, according to that equation.
Therefore, we can infer that the cost per pound of the apples is $1.75