Question

which property of equality does this equation illustrate?
$7 + r = r + 7$

• commutative property of multiplication
• associative property of addition
• commutative property of addition
• distributive property

Explanation:

The equation \(7 + r = r + 7\) shows that the order of adding 7 and \(r\) can be reversed without changing the result. The commutative property of addition states that for any two numbers \(a\) and \(b\), \(a + b = b + a\). The commutative property of multiplication involves multiplication (\(a\times b = b\times a\)), the associative property of addition involves grouping (\((a + b)+c = a+(b + c)\)), and the distributive property involves multiplying a sum by a number (\(a(b + c)=ab + ac\)). So this equation illustrates the commutative property of addition.

Answer:

C. Commutative property of addition