## Model Subtraction

## Opening

# Model Subtraction

Use the Hot Air Balloon interaction to model each problem and find the difference. Write your answer as an equation.

- Subtract a negative from a negative.

For example: −3 − (−7) - Subtract a negative from a positive.

For example: 9 − (−9) - Subtract a positive from a negative.

For example: −2 − 5 Subtract a positive from a positive.

For example: 2 − 8When you remove heat from air (subtract a positive number), what happens to the balloon?

- When you remove weight (subtract a negative number), what happens to the balloon?

INTERACTIVE: Hot Air Balloon