Chapter 4, Problem 3QC

To determine

To evaluate: $-7\left(-4\right)$

Answer to Problem 3QC

  $28$

Explanation of Solution

Given information:

  $-7\left(-4\right)$

Calculation:

We know product of numbers with same sign is always positive and product of numbers with opposite sign is always negative.

Product of the given expression can be calculated as shown:

  $-7\left(-4\right)=28\mathrm{...}\left[(-)·(-)=(+)\right]$