11-5 Subtracting Integers

Course 1

Warm UpWarm Up

Lesson PresentationLesson Presentation

Problem of the DayProblem of the Day

Warm UpFind 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

Course 1

11-5 Subtracting Integers

1

–7 83 –1

Problem of the Day

Jamal knows his average score for 3 science tests. If he adds the average and the amount that each score differs from the average, what will his sum be?

Course 1

11-5 Subtracting Integers

The average

Learn to subtract integers.

Course 1

11-5 Subtracting Integers

Course 1

11-5 Subtracting Integers

Subtracting Integers on a Number Line

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

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

Additional Example 1: Writing Integer Subtraction

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 addition modeled is –5 – (–9) = 4.

Course 1

11-5 Subtracting Integers

Check It Out: Example 1

Write the subtraction modeled on each number line.

A.

B.

–5–2

The subtraction modeled is –5 – 2 = –7.

(–3)–(–5)

The addition modeled is –3 – (–5) = 2.

–8 –7 – 6 –5 –4 –3 –2 –1 0 1

–6 –5 –4 –3 –2 –1 0 1 2 3 4 5

Course 1

11-5 Subtracting Integers

Additional Example 2A: Subtracting Integers

Find the difference.

4 – 6

4 – 6 = –2

(–6)4

–3 –2 –1 0 1 2 3 4 5

Course 1

11-5 Subtracting Integers

Additional Example 2B: Subtracting Integers

Find the difference.

3 – (–3)

–(–3) 3

3 – (–3) = 6

–1 0 1 2 3 4 5 6 7

Course 1

11-5 Subtracting Integers

Check It Out: Example 2A

Find the difference.

2 – (–5)

–1 0 1 2 3 4 5 6 7

– (–5) 2

2 – (–5) = 7

Course 1

11-5 Subtracting Integers

Check It Out: Example 2B

Find the difference.

3 – 6

3 – 6 = –3

(–6)

3

–3 –2 –1 0 1 2 3 4 5

Course 1

11-5 Subtracting Integers

Additional Example 3: Evaluating Integer Expressions

Evaluate a – 4 for a = 2.

a – 4 Write the expression.

2 – 4 Substitute 2 for a.

–2 Subtract.

Course 1

11-5 Subtracting Integers

Check It Out: Example 3

Evaluate b – 6 for b= 8.

b – 6 Write the expression.

8 – 6 Substitute 8 for b.

2 Subtract.

Course 1

11-5 Subtracting Integers

Lesson QuizFind 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

Insert Lesson Title Here

5

27,744 ft

12

Course 1

11-5 Subtracting Integers