Question

Indicate which property is illustrated in Step 4.

Step 1 9 - 3x - 9 + 4x = (9 - 3x) + (-9 + 4x)
Step 2 = (9 - 3x) + (4x - 9)
Step 3 = 9 + (-3x + 4x) - 9
Step 4 = 9 + (-3 + 4)x - 9
Step 5 = 9 + x - 9
Step 6 = x + 9 - 9
Step 7 = x + 0
Step 8 = x

Answer 1

@Isaiah.Feynman @campbell_st @mathgeek27 @mathmath333

Answer 2

@kirbykirby @texaschic101 @kl0723 @lee_actress @esshotwired