Negative Numbers

If the temperature is $10\,^\circ\text{C}$ and drops by $15\,^\circ\text{C}$, what is the final temperature?

-5 degrees C

On a number line, in which directions do you move to add and to subtract a number? Move to the right to ______, and move to the left to ______.

add, subtract

State the rule for adding a negative number.

Adding a negative number is the same as subtracting a positive number.

State the rule for subtracting a negative number.

Subtracting a negative number is the same as adding a positive number.

Evaluate: $-3 - (-7)$

4

Evaluate: $-8 + (-2)$

-10

Evaluate: $4 \times (-8)$

-32

Evaluate: $-20 \div (-2)$

10

Evaluate: $(-5)^2$

25

Evaluate: $-0.5 - 0.4$

-0.9

Evaluate: $4 \times (-0.2)$

-0.8

Evaluate: $1 - (-6) - 3$

4