Why does my child think (x + 2)(x + 3) = x² + 6?
Your child multiplies only the first terms and the last terms when expanding two brackets, such as (x + 2)(x + 3) = x² + 6.
Why children do it
Multiplying the first terms and the last terms looks complete, but each term in one bracket multiplies each term in the other: four multiplications. The middle two, 3x and 2x, are the ones missed. (x + 2)(x + 3) is x² + 5x + 6.
How to help at home
Ask them to draw a grid with one bracket along the top and one down the side: every box needs filling.
The right way
Expand: (x + 2)(x + 5)
- x² + 5x + 2x + 10x times x, x times 5, 2 times x, and 2 times 5.
- x² + 7x + 10Collect the x terms.
Find out where your child is
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Start the free checkRelated mistakes
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