Why does my child think 3x² × 4x³ = 7x⁵?
Your child adds the numbers in front when multiplying terms, such as 3x² × 4x³ = 7x⁵.
Why children do it
Children who have just learnt to add the powers sometimes add the numbers in front too. But the numbers multiply as usual: 3 × 4 is 12. Only the powers add, so 3x² × 4x³ is 12x⁵.
How to help at home
Ask them to multiply the numbers first, then the letters, as two separate steps.
The right way
Simplify: 3x² × 4x³
- 12x⁵Multiply the numbers, 3 × 4 is 12, and add the indices, 2 + 3 is 5.
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