Without delay, let's solve this. We've got 789 and we will be multiplying it by 9, that is, adding 789 to itself 9 times.
Step 1: 0 + 789 = 789
Step 2: 789 + 789 = 1578
Step 3: 1578 + 789 = 2367
Step 4: 2367 + 789 = 3156
Step 5: 3156 + 789 = 3945
Step 6: 3945 + 789 = 4734
Step 7: 4734 + 789 = 5523
Step 8: 5523 + 789 = 6312
Step 9: 6312 + 789 = 7101

So, 789*9 = 7101