Find each sum.

1. –4 + 6 2. 5 + 123. –3 + 3 4. –8 + 9

Give the opposite of each number.5. 7 6. –87. –3 8. 1

2 170 1

–7 83 –1

Do Now

2/9/2015 7-3 D Subtracting Integers

Move left on a number line to subtract a positive integer.

Move right on a number line to subtract a negative integer.

Subtracting Integers on a Number Line

Example 1

Write the subtraction modeled on each number line.

A.

B.

–8 –7 – 6 –5 –4 –3 –2 –1 0 1

–3–4

The subtraction modeled is –3 – 4 = –7.

–6 –5 –4 –3 –2 –1 0 1 2 3 4 5

(–5)– (–9)

The subtraction modeled is –5 – (–9) = 4.

LCCeave hange hange

Example 2

Find the difference.

4 – 6

4 – 6 = –2

(–6)

4

–3 –2 –1 0 1 2 3 4 5

Example 3

Find the difference.

3 – (–3)

–(–3) 3

3 – (–3) = 6

–1 0 1 2 3 4 5 6 7

Example 4

Evaluate a – 4 for a = 2.

a – 4 Write the expression.

2 – 4 Substitute 2 for a.

–2 Subtract.

Find each difference.

1. 8 – 5 2. –9 – (–3)

Evaluate x – (–7) for each value of x.

3. x = –2 4. x = 5

5. The peak of Mt. Everest is approximately

26,544 ft above sea level. The shore of the

Dead Sea is about 1,200 ft below sea level.

How much higher is the peak of Mt. Everest

than the shore of the Dead Sea?

–63

5

27,744 ft

12

Exit Ticket

1. Identify the difference. 9 – 6

A. 3

B. –3

C. 15

D. –15

2. Identify the difference. –11 – (–8)

A. 3

B. –3

C. 19

D. –19

3. Evaluate p – (–8) for p = –9.

A. 17

B. 1

C. –1

D. –17

4. Evaluate s – (–8) for s = 13.

A. 21

B. 5

C. –5

D. –21

5. A submarine is 150 feet below the sea level. An airplane is 1,000 feet above the sea level and directly above the submarine. What is the distance between the airplane and the submarine?

A. 850 ft

B. 1,000 ft

C. 1,150 ft

D. 1,500 ft

Homework

• Subtracting Integers W.S.