Distributive

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Maths.


Multiplication is distributive over addition

The distributive property of multiplication over addition means that brackets within expressions can be 'multiplied out' when the brackets contain additions.


Example

3 x (4 + 5) gives the same result as:

(3 x 4) + (3 x 5).


In the first case:

3 x (4 + 5)

= 3 x 9

= 27


In the second case:

(3 x 4) + (3 x 5)

= 12 + 15

= 27 as before.


Multiplication is also distributive over subtraction

The distributive property of multiplication over subtraction means that brackets within expressions can also be 'multiplied out' when the brackets contain subtractions.


Example

3 x (6 - 2) gives the same result as:

(3 x 6) - (3 x 2).


In the first case:

3 x (6 - 2)

= 3 x 4

= 12


In the second case:

(3 x 6) - (3 x 2)

= 18 + 6

= 12 as before.


See also