Subtracting Integers7th Grade Math

Pg. 103

DART statement:

I can subtract integers.

Subtract Integers

To subtract an integer, add its opposite.

What is the opposite of -7?

What is the opposite of 3?

Examples:

1. 4 – 9

4 + (-9)

-5

2. 7 – (-10)

7 + 10

17

Subtract Positive Integers

Find 8 – 13. (To subtract 13, add -13.)

8 + (-13)

-5

Try one on your own.

Find -10 – 7.

*To subtract 7, add -7.

-10 + (-7)

-17

Subtract Negative Integers

Find 1 – (-2). To subtract -2, add 2.

1 + 2

3

Find -10 – (-7)

-10 + 7 To subtract -7, add 7.

-3

Try these on your own.

4 – (-12) -15 – (-5) 18 – (-6)

Evaluate an Expression

Evaluate x – y if x = -6 and y = -5.

x – y

-6 – (-5)

-6 + 5

-1

Evaluate each expression if a=5, b=-8, and c=-9.

1.) b - 10 2.) a - b 3.) c - a