Download adding integers

NOTES
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INTEGERS
An integer is a whole number that is positive, negative or zero.
ADDING INTEGERS
Same sign, add and keep
Different signs, subtract
Take the sign of the “higher” number
Then it will be exact!
Same signs (both positive or both negative)
1. Add the numbers
2. Keep the sign of the numbers in the answer (sum).
12 + 5 = 17
23 + 64 = 87
-8 + -14 = -22
-76 + -52 = -128
Different signs (positive plus negative or negative plus positive)
1. Subtract the numbers.
2. Take the sign of the number with the greater absolute value as the sign
for the answer (sum).
(-6) + 13 = 7
76 + (-12) = 64
(-45) + 32 = -13
15 + (-64) = 49
SUBTRACTING INTEGERS
1. Keep the first number the same.
2. Change subtraction to addition.
3. Change the second number to its opposite.
4. Use the rules for adding integers.
19 – (-3) = 19 + 3 = 22
(-23) – 8 = -23 + (-8) = -31
(-10) – (-4) = -10 + 4 = -6
85 – 100 = 85 + (-100) = -15
MULTIPLYING & DIVIDING INTEGERS
1. Ignore the signs and multiply or divide the numbers
2. If…
SAME SIGN = POSITIVE
DIFFERENT SIGNS = NEGATIVE
6 x 5 = 30
(-9) x (-7)= 63
(-8) x 7 = -56
12 x (-5) = -60