Adding Integers with Opposite Signs: Using an Algorithm

This video tutorial teaches how to add integers with opposite signs without using a number line. It begins with a review of absolute values and their role in addition. The tutorial explains how to add integers with the same signs and then moves on to adding integers with opposite signs using a number line. A common mistake is addressed, and an algorithm is introduced to add integers with opposite signs by comparing absolute values. The video concludes with examples of applying the algorithm to larger integers.

What is the absolute value of -3?

• 3

• -3

• 0

• 6

When adding two positive numbers, in which direction do you move on the number line?

• Up

• Left

• Down

• Right

What is a common mistake students make when adding numbers with opposite signs?

• Thinking the sum is always positive

• Thinking the sum is always negative

• Assuming the sum has the same sign as the first number

• Assuming the sum is zero

How do you determine the sign of the sum when using the algorithm for adding integers with opposite signs?

• The sign of the number with the smaller absolute value

• The sign of the second number

• The sign of the first number

• The sign of the number with the larger absolute value

What is the result of adding 75 and -100 using the algorithm?

• 175

• -25

• -175

• 25