Why does my child solve x − 4 = 10 as x = 6?
Your child subtracts to undo a subtraction, instead of adding.
Why children do it
To get x on its own, the − 4 has to be undone, and the opposite of taking away is adding. Children who see a minus sign often take away again, because that's the sign in front of them. x − 4 = 10 means x is 4 more than 10, so x = 14.
How to help at home
Ask what undoes taking a number away. Adding it does, so the same number is added to both sides.
The right way
Solve: x − 7 = 12
- x = 19Add 7 to both sides, to undo taking 7 away.
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