Transcript ADDING REAL NUMBERS

ADDING REAL NUMBERS
Section 2.2
Algebra tiles can be used to add or subtract integers.
Remember integers are ...  4, 3, 2, 1, 0,1, 2, 3, 4,...



  1







.
  1


3
4



Example 1:
Use algebra tiles to represent











=



=

5
2   4
Use algebra tiles to represent

23

 =






=
6
zero
Neutral pairs have a value of _____.



=
0
Example 2:
A. Use algebra tiles to represent
5   3
and then cross out any neutral pairs.







+


=

=
2
B. Use algebra tiles to represent
6  4
and then cross out any neutral pairs.












=

=
2
C. Use algebra tiles to represent 5  4
and then cross out any neutral pairs.










  
1
 
D. Use algebra tiles to represent 4  6
and then cross out any neutral pairs.











=
2
E. Use algebra tiles to represent 2 
and then cross out any neutral pairs.

1
2
3

4

5
There are no
neutral pairs
=
 3
5
F. Use algebra tiles to represent 1  4
and then cross out any neutral pairs.




There are no
neutral pairs


=
5
Rules For Adding Two Signed Numbers:
A. Signs are the same –
Add the numbers
1. ______________________________________
Take the given sign
2.______________________________________
B. Signs are the different –
the numbers
1.Subtract
______________________________________
Take
the sign of the larger number
2.______________________________________
Example 3: Find each sum.
A. 2   8
Signs are
the same
10
Try these…
A. 3   12
15
B.
15   23
Signs are
different
8
C. 5  14
Signs are
different
9
Find each sum.
B.
17   32
15
C. 15  18
3
Example 4: Find each sum.
A.
1.3  2.5
1  1
   1 
B. 4  4 
1 1
2
1  1
4 4
4
2.5  1.3  1.2
1.2
C.
3.7   8.6
3.7  8.6  12.3
-12.3
D.
1
1
2
2
1
4  5
3
3
1
2 2
5 4 
3
3 3
2
3
Try these… Find each sum.
A.
9  3.7
5.3
C.
6.3   2.5
8.8
B.
 3
7   1 
 4
1
5
4
1  2
D. 4   7 
5  3
7
3
15