TalkingPencil

Perform mixed arithmetic operations of directed numbers

Follow this one with me, a step at a time. Try to guess each step first.
Worked example 1

Calculate: 8 + 8 × (−2)

Remember: Multiply before you add or subtract. Two numbers with the same sign have a positive product, and two with different signs have a negative product.

Common mistakes

  • Worked from left to right. Multiplication comes before addition and subtraction.
  • The size of the product is right, but its sign is not. Same signs give a positive product and different signs give a negative one, and subtracting a negative number means adding.
  • The size of the answer is right, but the sign is the opposite. Check the sign at the last step.