You can do 21+(2 w) because 2w is equal to 2 w
FYI *=Multiplication
Distributive property means that we can take factor in from of parenthesis. 2l+2w=2(l+w) The number is not changed, because factor can be easily multiplied by every argument in front of parenthesis.
Using the distributive property, 2 l + 2 w can be rewritten as 2 ( l + w ) by factoring out the common factor of 2. This shows both expressions are equivalent. The distributive property helps simplify expressions by factoring out common terms.
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