Final answer:
The property under multiplication used in the equation -2/3 × 1 = 1 × -2/3 = -2/3 is the commutative property of multiplication.
Step-by-step explanation:
The property under multiplication used in the equation -2/3 × 1 = 1 × -2/3 = -2/3 is the commutative property of multiplication.
The commutative property states that the order of the numbers being multiplied does not affect the result. In this case, whether we multiply -2/3 by 1 or 1 by -2/3, we get the same result of -2/3.
This property holds true for all real numbers. For example, 2 × 3 is the same as 3 × 2, and (-4) × (-3) is the same as (-3) × (-4), both resulting in a positive product.