Solving Addition and Subtraction Equations

1
Solving Addition and Subtraction Equations

• Lesson 2-6

2
Procedure

• Isolate the variable by performing the inverse
  operation on that variable.
• The inverse of subtraction is adding. The
  inverse of adding is subtracting.
• Perform the same operation on the side of the
  equal sign that does not have a variable.

3
Example
We want to get the y by itself. Perform the
inverse operation. The inverse of adding is
subtracting.
y 13 25
- 13
- 13
Do the same operation on the other side of the
equal sign.
y 12
4
Check the answer in the original equation.
y 13 25
12 13 25
25 25
5
Example 2
To get k by itself, we perform the inverse
operation. The opposite of minus 12 is plus
12.
k 12 4
12
12
k 16
6
Check
k 12 4
16 12 4
4 4
7
Homework Time