An equation says two things are equal. To solve it, find the value of the letter that makes it true. Keep the equation balanced: whatever you do to one side, do to the other.
Use the inverse operation to undo what is happening to x. In x + 12 = 31, subtract 12 from both sides: x = 19. In 6x = 30, divide both sides by 6: x = 5. Always check by substituting your answer back in.
Worked example
Solve x − 4 = 7
- 4 is being taken away from x, so add 4 to both sides.
- x = 7 + 4.
Answer:x = 11
Key words
- equation
- a statement that two things are equal
- solve
- find the value of the unknown
- inverse operation
- the operation that undoes another
Practise this
New questions every time.
Common Core-referenced: 6.EE.B.7