Adding Integers
1) If the numbers have the same
sign, add the absolute values and
keep the sign.
2) If the numbers have different
signs, subtract the absolute values
and take the sign of the larger
absolute value.
Subtracting Integers
1. Rewrite subtraction problem as addition
2. Copy first number in problem (It never
changes!)
3. Change the subtraction sign to addition.
4. Change the number after the subtraction sign
to its inverse (opposite).
(If the number was negative, it becomes
positive; if the number was positive, it
becomes negative.)
5. Follow rules for addition of integers.
Examples: Write an expression and solve.
1) A team gains 20 yards. Then they lose 7 yards.
2) A team gained 5 yards on their first play. Then
they lost 6 yards. Find their yardage.