1. MCC6.EE.7 -----SOLVE EQUATIONS
How do I solve one-step equations? (In 6th grade, these equations contain only one-variable.)
MCC6.EE SOLVE EQUATIONS

2. IMPORTANT INFO: INVERSE = OPPOSITE
ADDITION AND SUBTRACTION ARE INVERSE OPERATIONS
Adding and Subtracting “UNDO” each other
Equations have two sides.
To solve an equation, you need to get the variable alone on one side of the equal sign.
(this is called isolating the variable)

3. IMPORTANT INFO: INVERSE = OPPOSITE
ADDITION AND SUBTRACTION ARE INVERSE OPERATIONS
Adding and Subtracting “UNDO” each other
Equations have two sides.
To solve an equation, you need to get the variable alone on one side of the equal sign.
(this is called isolating the variable)

4. (1) X + 54 = 90 (2) 49 = 12 + y ADDITION EQUATIONS - 12 - 12 - 54 - 54
zero pair isolates the variable
zero pair isolates the variable
ADDITION EQUATIONS
(1) X + 54 = 90
(2) 49 = 12 + y
- 12
- 12
- 54
- 54
To isolate the variable, subtract 54 from both sides of the equation.
To isolate the variable, subtract 12 from both sides of the equation.
37 = y
X = 36
Check by substituting x with 36.
Check by substituting y with 37.
= 90
= 49
When x is 36, the equation is true.
When y is 37, the equation is true.

5. SUBTRACTION EQUATIONS
zero pair isolates the variable
zero pair isolates the variable
SUBTRACTION EQUATIONS
(1) p - 8 = 9
(2) 3 = x - 16
+16 +8
+16 +8
To isolate the variable, add 8 to both sides of the equation.
To isolate the variable, add 16 to both sides of the equation.
19 = x
p = 17
Check by substituting p with 17.
Check by substituting x with 19.
= 9
= 3
When p is 17, the equation is true.
When x is 19, the equation is true.

6. And equations with decimals?
zero pair isolates the variable
zero pair isolates the variable
(2) x = 8
(1) a = 4.8
- 4.5
+2.7
+2.7
- 4.5
To isolate the variable, add 2.7 to both sides of the equation.
To isolate the variable, subtract 4.5 from both sides of the equation.
a = 7.5
x = 3.5
Check by substituting a with 7.5.
Check by substituting x with 3.5.
7.5 – 2.7 = 4.8
= 8
When a is 7.5, the equation is true.
When x is 3.5, the equation is true.

7. And equations with decimals?
zero pair isolates the variable
zero pair isolates the variable
(3) t = 12.59
(4) 15.2 = s
-7.8
-7.8
+6.08
+6.08
To isolate the variable, add 6.08 to both sides of the equation.
To isolate the variable, subtract 7.8 from both sides of the equation.
7.4 = s
t = 18.67
Check by substituting s with 7.4.
Check by substituting t with
= 15.2
18.67 – 6.08 = 12.59
When s is 7.4, the equation is true.
When t is 18.67, the equation is true.