Download POSITIVE AND NEGATIVE NUMBERS

POSITIVE AND NEGATIVE NUMBERS
ADDITION
LIKE signs – Add the unsigned numbers and keep the original sign.
Examples:
7
3
10 or 8
6
14
UNLIKE signs – Subtract the unsigned numbers and keep the sign of the larger.
Examples: 5
9
4 or
8
9
1
SUBTRACTION
Change subtraction to addition, but adding the opposite of the second number. Then follow the rules for
addition (above).
7
Examples:
5 8
10 5
3
8 8
9 7
10,
5
3
5,
7
8
10
8 ,
9 ,
3
5
2
18
5
8
9
6
13
MULTIPLICATION and DIVISION
LIKE signs – Multiply the unsigned numbers and the answer will be positive (the negatives cancel).
Examples:
2 3
6, 8 9
72, UNLIKE signs – Multiply the unsigned numbers and the answer will be negative.
Examples:
5 7
35 2 8
16
and OR and and OR and Helpful hints:
In multiplication and division two negative signs cancel out and the answer is positive—
whenever there are an even number of negative signs the final answer will be positive.
In multiplication and division if there is only one negative sign there is nothing to cancel it from
the problem and the answer will be negative – whenever there are an odd number of negative
signs the final answer will be negative.
PRACTICE FOR POSITIVE AND NEGATIVE SIGNED NUMBERS
1)
4
3
2)
4
4)
4
2
5)
4
3
6)
3
7)
6
6
8)
6
6
9)
18
9
10)
6
11)
6
7
4
4
13)
16)
3
3
0
6
19)
4 3
22)
6 ∙ 2
3
4
15)
17)
5
12
18)
20)
4 ∙3
21)
23)
4 ∙8
24)
3 27)
6 5
30)
45 26)
1
28)
9
3
29)
16
32)
12
36
31)
15 34)
4 4
35)
37)
3
6
4
6
6
0
6 3 3
2
36)
6 38)
39)
6
42)
2
7
45)
0
2
2
13
41)
7
43)
7
6
44)
8
2)
5)
8)
11)
14)
17)
20)
23)
26)
29)
32)
35)
38)
41)
44)
5
2
ANSWERS
-1
-7
-12
-10
-6
-7
-12
-32
18
4
-2
-9
-9
-12
-6
3
33)
4
4 5
40)
18
6
5
6
1
7
2
0
3
-7
6
12
-12
-9
-3
-5
-1
3
-11
1
12)
3
0
9 1)
4)
7)
10)
13)
16)
19)
22)
25)
28)
31)
34)
37)
40)
43)
4
14)
25)
3
3)
3)
6)
9)
12)
15)
18)
21)
24)
27)
30)
33)
36)
39)
42)
45)
1
2
9
-3
0
-6
-9
6
-30
15
5
1
0
-5
0
6
6