Let's roll up our sleeves and solve this. We have 543 and we're going to multiply it by 19, essentially adding 543 to itself 19 times.
Step 1: 0 + 543 = 543
Step 2: 543 + 543 = 1086
Step 3: 1086 + 543 = 1629
Step 4: 1629 + 543 = 2172
Step 5: 2172 + 543 = 2715
Step 6: 2715 + 543 = 3258
Step 7: 3258 + 543 = 3801
Step 8: 3801 + 543 = 4344
Step 9: 4344 + 543 = 4887
Step 10: 4887 + 543 = 5430
Step 11: 5430 + 543 = 5973
Step 12: 5973 + 543 = 6516
Step 13: 6516 + 543 = 7059
Step 14: 7059 + 543 = 7602
Step 15: 7602 + 543 = 8145
Step 16: 8145 + 543 = 8688
Step 17: 8688 + 543 = 9231
Step 18: 9231 + 543 = 9774
Step 19: 9774 + 543 = 10317

So, 543*19 = 10317