Which equation demonstrates the commutative property of addition?

Which equation demonstrates the commutative property of addition?

• A. a - b = b - a
• B. a + b = a + b
• C. a + b = b + a
• D. a + b = a - b

Answer: (C)

Swapping the order of addends does not change the result. This is the commutative property of addition. The expression a + b = b + a shows this principle in action: for any numbers a and b, adding them in the reverse order yields the same sum. For example, if a is 3 and b is 5, both 3 + 5 and 5 + 3 equal 8. Other forms don’t illustrate this idea: a - b = b - a would not hold true in general, since subtraction depends on order. A + b = a + b is always true but simply restates that a number plus another equals itself, not that the order can be swapped. A + b = a - b would usually be false. So the expression that best demonstrates the commutative property is the one where a + b equals b + a.

Swapping the order of addends does not change the result. This is the commutative property of addition. The expression a + b = b + a shows this principle in action: for any numbers a and b, adding them in the reverse order yields the same sum. For example, if a is 3 and b is 5, both 3 + 5 and 5 + 3 equal 8.

Other forms don’t illustrate this idea: a - b = b - a would not hold true in general, since subtraction depends on order. A + b = a + b is always true but simply restates that a number plus another equals itself, not that the order can be swapped. A + b = a - b would usually be false. So the expression that best demonstrates the commutative property is the one where a + b equals b + a.