OK, let's work through this together. We're starting with 285 and we're going to multiply it by 19, which means we add 285 to itself 19 times.
Step 1: 0 + 285 = 285
Step 2: 285 + 285 = 570
Step 3: 570 + 285 = 855
Step 4: 855 + 285 = 1140
Step 5: 1140 + 285 = 1425
Step 6: 1425 + 285 = 1710
Step 7: 1710 + 285 = 1995
Step 8: 1995 + 285 = 2280
Step 9: 2280 + 285 = 2565
Step 10: 2565 + 285 = 2850
Step 11: 2850 + 285 = 3135
Step 12: 3135 + 285 = 3420
Step 13: 3420 + 285 = 3705
Step 14: 3705 + 285 = 3990
Step 15: 3990 + 285 = 4275
Step 16: 4275 + 285 = 4560
Step 17: 4560 + 285 = 4845
Step 18: 4845 + 285 = 5130
Step 19: 5130 + 285 = 5415

So, 285*19 = 5415