11-5 subtracting integers lesson presentation lesson presentation lesson quizzes lesson quizzes
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11-5 Subtracting Integers
Preview of MA.7.A.3.1 Use and justify the rules for…subtracting…integers.
Preview of MA.7.A.3.2 Subtract…integers,…including solving problems in everyday contexts.
Sunshine State Standards
11-5 Subtracting Integers
Move left on a number line to subtract a positive integer.
Move right on a number line to subtract a negative integer.
Confused???
Subtracting Integers on a Number Line
11-5 Subtracting Integers
Slash & DashWhen subtracting a positive number – use
“SLASH & DASH”-4 – 3 =
Keep the -4
SLASH the subtraction symbol (+)
Mark a DASH on the 3 to make it negative
-4 + -3 = -7
11-5 Subtracting Integers
Slash & SlashWhen subtracting a negative number – use
“SLASH & SLASH”-4 – -3 =
Keep the -4
SLASH the subtraction symbol (+)
SLASH the -3 to make it a positive 3
-4 + +3 = -1
11-5 Subtracting Integers
Keep, Change, ChangeSome teachers teach Slash/Slash or
Slash/Dash as
KEEP, CHANGE, CHANGE
11-5 Subtracting Integers
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 subtraction modeled is –5 – (–9) = 4.
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 subtraction 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
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
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
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
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
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.
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.
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
5
27,744 ft
12