2. 1’s tell your partner what is the goal in an equation.

3. Use Algebra Tiles to model
8 + x = 15
Write the equation that matches the model and solve + = = +

5. Solving Addition Equations
Step 1: isolate the variable by using the inverse operation of the constant to both sides
Step 2: Subtract (remember integer rules)
Step 3: bring down your variable and your difference
½ + x = 3/5
Step 1: ½ + x = 3/5
- ½ ½
= 1/10
Step 2:
Step 3:
X = 1/10

7. Explain how you isolate the variable.
2’s tell your partner what is the name of the step the gets the variable alone called?
Explain how you isolate the variable.

8. Error Analysis 36 + y = 97 -36 = +36 y = 133 Identify my error
= +36
y = 133
Identify my error
Correct the error and solve for y

9. Solving Subtraction Equations
Step 1: isolate the variable by using the inverse operation of the constant to both sides
Step 2: Add (remember integer rules)
Step 3: bring down your variable and your sum
x - 3 = -8
Step 1: x - 3 = -8
+ (3) + (3)
= -5
Step 2:
Step 3:
X =

10. Subtraction Equations
To solve subtraction equations, add the same number to both sides of the equation.
X – 15 = 22
+15 = +15
x = 37
Higher Level:
x - (-5) = 12
+(-5) = +(-5)
x = 7

11. Assessment Prompt
Discuss with your partner: how you would solve the problems below:
-12 + y = – x = -14
(Easy trick: use the rule of integers and turn your subtraction problem into an addition problem by adding the additive inverse (opposite) )

12. Higher level Practice -5 – x = 12 Turn into addition
5 + x + -2 = 18 You may have to combine like terms

13. What is the verbal model for this equation?