foundations of

Distributive Property

Initial Definition

The distributive property of multiplication over addition: Multiplying a sum by a number is the same as multiplying each addend by the number and then adding the products.


The distributive property of multiplication over subtraction: Multiplying a difference by a number is the same as multiplying the subtrahend and the minuend by the number and then subtracting the products.


Examples

The distributive property of multiplication over addition.


3(4 + 2) = 3x4 + 3x2

3x6 = 12 + 6

18 = 18

(Both sides have a result of 18.)



The distributive property of multiplication over subtraction.


3(4 - 2) = 3x4 - 3x2

3x2 = 12 - 6

6 = 6

(Both sides have a result of 6.)


Another Example

Multiplication is NOT distributive over multiplication.


3(4 x 2) ≠ 3x4 x 3x2

3x8 ≠ 12 x 6

24 ≠ 72

(Both sides do not have the same result.)



In this case the 3 is distributed to the four OR the two, NOT BOTH.


3(4 x 2) = 3x4 x 2

3x8 = 12 x 2

24 = 24

(Both sides have a result of 24.)


3(4 x 2) = 4 x 3x2

3x8 = 4 x 6

24 = 24

(Both sides have a result of 24.)