Which equation demonstrates the multiplicative identity property of one?

Which equation demonstrates the multiplicative identity property of one?

• A. A × 1 = A
• B. A × 1 = 0
• C. A × 0 = A
• D. A × A = 1

Answer: (A)

Multiplicative identity means that multiplying any number by 1 leaves that number unchanged. The expression that shows this is a × 1 = a. For example, 8 × 1 = 8. The other possibilities don’t fit this idea: multiplying by 0 always gives 0, not the original number; multiplying a number by itself equals 1 only in special cases (like when the number is 1 or -1), not for every a; and a × 1 = 0 would force a to be 0, which isn’t the general rule.

Multiplicative identity means that multiplying any number by 1 leaves that number unchanged. The expression that shows this is a × 1 = a. For example, 8 × 1 = 8.

The other possibilities don’t fit this idea: multiplying by 0 always gives 0, not the original number; multiplying a number by itself equals 1 only in special cases (like when the number is 1 or -1), not for every a; and a × 1 = 0 would force a to be 0, which isn’t the general rule.