Students will learn to subtract integers. If the signs are the same, add the numbers and keep the sign; if different, subtract the numbers and keep the sign of the bigger number. Exceptions are that -3 - (+2) = -5 and -3 - (-2) = -1. Word problems provide practice subtracting integers, such as finding a checking balance after a deposit and payment, or how much debt remains after part is forgiven.

1. Lesson 33
OBJ: STUDENTS WILL SUBTRACT INTEGERS.

2. Notes 33
The signs are the same – add and keep the sign
5 + 5 = 10 -2 + (-3) = -5
The signs are different – subtract and keep the biggest sign
5 + (-2) = 3 -9 + 2 = 7
Exceptions:
-3 – (+2) = -5 -3 – (-2) = -1
-3 + (-2) = -5 -3 + 2 = -1

3. Word Problems
Jocelyn has a checking balance of $1286. In the mail she receives a
rebate check for $25 and a utility bill for $128. She deposits the rebate
and writes a check for the bill. Write an equation with integers for the
situation and find her checking balance after transactions.
Victor owed $328. His creditor forgave (subtracted) $100 of the debt.
Write an equation for the situation and find out how much Victor still
owes.