7th Grade Math

(Marvins-Underground-K-12) #1
Subtracting Integers
To subtract an integer,
add its opposite.


  • 9 - (-4) = - 9 + 4
    = - 5


Subtract Like Fractions


Subtract. Write in simplest form.
_^9
10


  • _^1
    10


0101102103104105106107 108109 1

1
109 10

_^9
10


  • ^1
    10
    =
    ^9 -^1
    10
    Subtract the numerators.


= _^8
10
Simplify.

= _^4
5
Simplify.


  • _^5
    8

    • _^3
      8

      • 1 1 0

        • 8
          2







  • 8
    3

  • 8


3


  • 8
    5

  • 8


4


  • 8
    5

  • 8
    6

  • 8
    7

  • 8

  • _^5
    8

  • ^3
    8
    = -
    ^5
    8



  • (- _^3
    8


(^) ) To subtract ^38 , add - ^38.



  • 5 + (-3)
    _
    8
    Add the numerators.


= - _^8
8
Simplify.

= - 1 Simplify.

Find _^5
8


  • _^7
    8
    .


1
8

2
8

3
8

4
8

5
8

5
8

6

(^08)
1
8
2
8
7
8










_^5
8


  • ^7
    8
    =
    ^5 -^7
    8
    Subtract the numerators.


= - _^2
8
Simplify.

= - _^1
4
Simplify.

Check - _^2
8
+ _^7
8
= _^5
8

d. - _^5
9


  • ^2
    9
    e. -
    ^11
    12

    • (- _^5
      12




(^) ) f. - _^3
4



  • ^1
    4
    g.
    ^59 - ^2
    9
    h.
    1211 - ^5
    12
    i.
    107 - _^3
    10


140 Rational Numbers

139_156_C3L2_895130.indd 140 12/31/09 12:37 PM

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