Example with audio

1. Two-step Equations
 Using do/undo boxes!!!
 The “do” side of the box represents the mathematical
operations (+,-,x or ÷ ) with the numbers on the same side
of the equation with the variable.
 The “undo” represents completing the inverse operations
or the opposite operation of the “do” side.
 This should help you solve equations more efficiently.

2. 2x = -2
Step 4: Follow the flow of the arrows and complete
steps on undo side of chart to solve for the
unknown variable.
Answer: 2x means “multiply 2”
Answer: “subtract 1”
2x - 1 = -3
Step 1: Identify number and operation
closest to variable first. Input this on do side
of chart.
Example 1
Step 2: Identify second number and
operation on same side with variable.
Step 3: Opposite operation of “do” steps go on
undo side. Make sure you work in reverse order
by undoing the last step first in the chart. So,
write “Add 1” first, then above write “Divide 2”.
multiply 2
subtract 1
Divide 2
Add 1
x = -1
+ 1 + 1
2 2

3. + 4 + 4
Answer: subtract 4
Step 1: Identify number and operation
closest to variable first. Input this on do side
of chart.
Example 2
Step 2: Identify second number and
operation on same side with variable.
divide 3
subtract 4
multiply 3
add 4
x = 36
4 8
3
x
 
3
· ·3
Step 4: Follow the flow of the arrows and complete
steps on undo side of chart to solve for the
unknown variable.
Step 3: Opposite operation of “do” steps go on
undo side. Make sure you work in reverse order
by undoing the last step first in the chart. So,
write “Add 4” first, then above write “Multiply 3”.

4. EXAMPLE 3
-3y - 5 = -20
multiply -3
Subtract 5
What steps go on the do side of the chart to solve this
two –step equation?
-3y means
multiply by -3
Subtract 5
Fill in undo side.
• Remember- opposite operations of steps are written on
“undo” side of chart.
• Follow flow of arrows and work in reverse order of “do”
side.
Divide - 3
Add 5
Solve this problem using your do/undo box: Answers on next slide!!!

5. EXAMPLE 3
-3y - 5 = -20
multiply -3
Subtract 5
Divide – 3
Add 5
+ 5 + 5
-3y = -15
-3 -3
y = 5

6. + 4 + 4
Example 4
divide -3
subtract 4
add 4
multiply 3