Why does my child change only one side of an equation?
Your child does something to one side of the equation but not the other.
Why children do it
An equation is a balance: both sides are equal, and they only stay equal if whatever happens to one side happens to the other. Children busy getting x on its own often do a step to x's side and forget the other side, especially if they've learnt steps as moving numbers around rather than doing the same to both sides.
How to help at home
After each step, ask "what did you do to the other side?" Whatever is done to one side is done to both.
The right way
Solve: 3x + 5 = 17
- 3x = 12Subtract 5 from both sides: 17 - 5 is 12.
- x = 4Divide both sides by 3.
Find out where your child is
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Start the free checkRelated mistakes
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