Why does my child think (x − 2)(x − 3) = 0 gives x = −2 or x = −3?
Your child takes the number in each bracket as a solution without changing its sign, such as (x - 2)(x - 3) = 0 giving x = -2 or x = -3.
Why children do it
The numbers in the brackets are right there, so it's tempting to take them as the answers. But each bracket has to come to 0: x − 2 = 0 means x = 2. Putting the answer back in the bracket checks it.
How to help at home
Ask them to put their answer back in the bracket: does x - 2 come to 0?
The right way
Solve: (x − 2)(x − 3) = 0
- x − 2 = 0 or x − 3 = 0One of the brackets must be 0.
- x = 2 or x = 3Solve each one.
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