Transcript Adding and Subtracting Integers

Objective
Add and subtract integers
Rules for adding integers
1. Same Sign
2. Different Signs
Add numbers
Subtract numbers
Keep sign
Keep sign of largest
number
Rules for subtracting integers
First change to addition then
follow addition rules
Evaluate the expression
-6 + (-3)
same
6+3
-99
-6 + (-3)
Write the problem
Draw arrows to signs &
determine process to use
Same sign add the
absolute value of
number
Keep the sign
Evaluate the expression
8 + (-7)
Different
8-7
1
8 + (-7)
Write the problem
Draw arrows to signs &
determine process to use
Opposite sign subtract
the absolute value of
number
Keep the sign of the
largest number
Evaluate the expression
-5 + 4
different
5-4
-1
1
-5 + 4
Write the problem
Draw arrows to signs &
determine process to use
Different signs subtract
the absolute value of
number
Keep the sign of
largest number
Evaluate the expression 2 - 15
2 - 15
2 + -15
opposite
15 - 2
-13
13
Write the problem
Separate number and
sign then insert a “+”
Draw arrows to
signs to show what
to do
Subtract
Keep sign of largest
number
Evaluate the expression 12 - (-6)
12 - (-6)
12 + 6
same
12 + 6
18
Write the problem
Combine the 2 negatives to
make positive
Draw arrows to signs to
show what to do
Same signs add
Keep sign
Evaluate the expression g - h if g = -2 and h = -7
g-h
Write the problem
-2 - (-7)
Replace g with -2
and h with -7
-2 + 7
different
Combine the two negatives
to make a positive
Draw arrows to signs to
show what to do
Evaluate the expression g - h if g = -2 and h = -7
-2 + 7
different
7-2
+5
5
Different signs
subtract
Keep sign of largest number