Chapter 1 - Some Basic Concepts of Arithmetic and Algebra - 1.4 - Integers: Multiplication and Division - Problem Set 1.4 - Page 26: 48

-12

Because multiplication is before addition or subtraction in order of operations, we first multiply and then we add and subtract. We see that we are multiplying a positive number by a negative number in this problem. Recall, when we multiply a positive by a negative, the answer will always be negative. Thus, we obtain: $7(-4)-8(-7)+5(-8)=-28-(-56)+(-40)=-28+56-40=-12$