Explain how you could use a number line to show that -4+3 and 3+ -4 have the same value. Which property of addition states that the sums are equivalent?
For -4+3, plot -4 on the number line and move up three steps. For 3+-4, plot 3 on the number line and move back four steps. You should end at -1 both times. This demonstrates the commutative property of addition.