1.
Grade 7 – Mathematics
Quarter I
SUBTRACTION OF INTEGERS

2.
• determine the opposite of the given
integer; and
• apply the rules in subtracting
integers.

3.
Rules in Adding Integers:
Fill in the blank.
Same signs, _________ and keep.
Different signs, ____________ ,
Keep the sign of bigger _________________.
ADDSUBTRACT
ABSOLUTE
VALUE
ADD
SUBTRACT
ABSOLUTE VALUE

4.
“What’s the OPPOSITE?”
-10
14
-9
7
31. -3 =
2. 10 =
3. -14 =
4. 9 =
5. -7 =

5.
SUBTRACTION OF INTEGERS
“adding the opposites”
a - b a - (-b)
a
KEEP – CHANGE - CHANGE
+ (-b)
KEEP
CHANGE
CHANGE
a + b
KEEP
CHANGE
CHANGE
- proceed to ADDITION rule

6.
SUBTRACTION OF INTEGERS
“adding the opposites”
KEEP – CHANGE - CHANGE
GIVEN KEEP CHANGE
(adding)
CHANGE
(opposite)
ANSWER
8 - 11
-12 – (-16)
10 – (- 6)
-14 - 8
8 + (-11) 8 + (-11) = -3
-12 + 16 -12 + 16 = 4
10 + 6 10 + 6 = 16
-14 + (-8) -14 + (-8)= -22

7.
SUBTRACTION OF INTEGERS
2. -7 - 10 =
1. 3 - (-5) = = 83 + 5
= -17-7 + (-10)
3. -40 - 20 = = -60-40 + (-20)
4. 15 - 9 = = 615 + (-9)
5. 10 – 9 – (-4) =
= 14
10 +(-9)+ 4
+(-9) = 5

8.
SUBTRACTION OF INTEGERS
-15 - ______ = 10
= -15 + (-10)-15 - 10
1. What number must be subtracted from -15 to
get 10?
= -25
(-25)
8 - ______ = -4
= 8 + 48 - (-4)
2. What number must be subtracted from 8 to
get -4?
= 12
12

9.
Test Yourself.
2. -24 - 9 =
1. 2 - (-5) =
4. 3 - (-6) - 8 =
3. -12 - (-18) =
5. 9 - (-1) - (-3) =

10.
Answer Key
1. 7
2. -33
3. 6
4. 1
5. 13