Answer:
That is 52 calories per apple.
Step-by-step explanation:

The sign at the end changes because both sides of the equation are being divided by a negative number.
The worksheet pic is not clear
Using the equation P=a+b+c , you just need to plug in.
4a-2b + 7a-3 + 9a - 4
Combine like terms.
20a-2b-7