Download 1. Add numbers 2. Keep the sign 1. Subtract smaller number from

Lycée Jean-Piaget - Neuchâtel
2015-2016
Add and Subtract on 1. Sign rule for adding: 2. Example of application: −5 + −3 7 + 4 Do the signs match? Yes Do the sings match? Yes 1. Add numbers
5 + 3 = 8 7 + 4 = 11 2. Keep the sign −8 11 −7 + 2 −4 + 6 Do the signs match? No Do the sings match? No 1. Subtract smaller number from larger one 7 − 2 = 5 6 − 4 = 2 2. Keep the sign of the larger number
−5 2 Mathematics
1MPES2
Chapter 1
Lycée Jean-Piaget - Neuchâtel
2015-2016
4 + −3 7 + −10 Do the signs match? No Do the sings match? No 1. Subtract smaller number from larger one 4 − 3 = 1 10 − 7 = 3 2. Keep the sign of the larger number 1 −3 3. Sign rule for subtracting: Trick :
• Change the subtraction problem to an addition
problem
• By adding the opposite
• 6 è - 6
- 6 è 6
• Then apply the sign rule for addition
4. Example of application: 8−3
8 + −3
Opposite signs
8−3=5
9 − −4
9 + +4
Same signs
9 + 4 = 13
Keep the sign
13
−6 − −2
−6 + +2
Opposite signs
6−2=4
Keep sign of the larger number
5
−4 − 6
−4 + −6
Same signs
4 + 6 = 10
Keep the sign
−10
Mathematics
Keep sign of the larger number
−4
1MPES2
Chapter 1
Lycée Jean-Piaget - Neuchâtel
2015-2016
5. Practice exercises: Exercises for addition: 4 + −1 = 3 −8 + −1 = −9 −6 + 8 = 2 −5 + 3 = −2 −4 + −1 = −5 −5 + 7 = 2 −1 + −6 = −7 −2 + −7 = −9 Exercises for Subtraction: 1 − 3 = 1 + −3 = −2 4 − −1 = 4 + +1 = 5 −6 − −8 = −6 + +8 = 2 −3 − 3 = −3 + −3 = −6 7 − 7 = 7 + −7 =0 −7 − −5 = −7 + +5 = −2 3 − −1 = 3 + +1 = 4 6 − 3 = 6 + −3 = 3 −1 − 8 = −1 + −8 = −9 2 − 3 = 2 + −3 = −1 Mathematics
1MPES2
Chapter 1