Why does my child solve 4(x − 2) = 12 as x = 14?
Your child forgets to divide by the number in front of the brackets.
Why children do it
The 4 in front of the brackets multiplies everything inside, so it has to be undone too. Children who just drop the brackets and carry on forget it was ever there, and solve x − 2 = 12. Dividing both sides by 4 first gives x − 2 = 3, so x = 5.
How to help at home
The number in front of brackets multiplies everything inside. Ask what 4 lots of (x - 2) would be.
The right way
Solve: 3(x + 4) = 21
- x + 4 = 7Divide both sides by 3.
- x = 3Subtract 4 from both sides.
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