Why does my child think 5(x + 4) = 5x + 4?
Your child multiplies only the first term inside the brackets.
Why children do it
The number outside the brackets multiplies everything inside, not just the first term. Children who multiply the x and copy the rest are treating the brackets as if they reached only the first term. 5(x + 4) is 5 × x + 5 × 4, which is 5x + 20.
How to help at home
Draw an arrow from the number outside the brackets to each term inside: every term gets multiplied.
The right way
Expand: 5(4x + 4)
- 5 × 4x + 5 × 4Multiply each term inside by 5.
- 20x + 20Work out each one.
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