Zero Product Property
Multiplication has two additional properties. The first is the Zero
Product Property. This says that any number multiplied by 0 is equal to
0. For any number a, the following are always true:
For example,
3×0 = 0.
4, 567, 892, 435×0 = 0.
Because multiplication commutes, if you are multiplying a long string of
numbers that contains 0, you can move 0 to the beginning of the expression:
4×234×7×9×16×0×54 = 0×4×234×7×9×16×54
Because multiplication associates, this expression is equal to:
0×(4×234×7×9×16×54) = 0.
Thus, when multiplying any string of numbers, if 0 is one of
the numbers, then the answer is always 0.
Distributive Property of Multiplication over Addition
The final property of multiplication is the Distributive Property of
Multiplication over Addition. This property says that for any numbers a,
b, and c, the following is always true:
a×(b + c) = (a×b) + (a×c).
For example,
3×(5 + 1) = (3×5) + (3×1). We can see that this is true because
3×(5 + 1) = 3×6 = 18 and
(3×5) + (3×1) = 15 + 3 = 18.
Examples
Just like the properties of addition, these properties of multiplication can be
used in any order. Here are some examples to make the properties more
familiar:
Example 1.2×13×5 = ?
Commutative Property: 2×13×5 = 2×5×13
2×5×13 = 10×13 = 130
Example 2.8×(5×9) = ?
Associative Property: 8×(5×9) = (8×5)×9
(8×5)×9 = 40×9 = 360
Example 3.43×9×0×7 = ?
Zero Product Property: 43×9×0×7 = 0
Example 4.1×591 = ?
Identity Property: 1×591 = 591
Example 5.6×(2 + 20)
Distributive Property: 6×(2 + 20) = (6×2) + (6×20)
(6×2) + (6×20) = 12 + 120 = 132