8th Grade · Expressions & Equations
Isolate
8.EE.C.8b
Definition
To get a variable by itself on one side of an equation using inverse operations. This is the goal when solving and the first step in substitution.
Teach it
Where it is taught, with guided notes, practice, homework, an exit ticket and an interactive Teacher Deck.
Examples
- 3x+6 = 15: subtract 6 to get 3x = 9, divide by 3 to get x = 3.
- Solve x+y = 7 for y: y = 7-x.
Key rule
Use inverse operations to move every other term away from the variable.
Memory hook
Get the variable alone on one side.