Alright, let's solve this math problem step by step. First, we have the number 432. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 90. So, we're going to take the number 432 and add it to itself 90 times.
Step 1: 0 + 432 = 432
Step 2: 432 + 432 = 864
Step 3: 864 + 432 = 1296
Step 4: 1296 + 432 = 1728
Step 5: 1728 + 432 = 2160
Step 6: 2160 + 432 = 2592
Step 7: 2592 + 432 = 3024
Step 8: 3024 + 432 = 3456
Step 9: 3456 + 432 = 3888
Step 10: 3888 + 432 = 4320
Step 11: 4320 + 432 = 4752
Step 12: 4752 + 432 = 5184
Step 13: 5184 + 432 = 5616
Step 14: 5616 + 432 = 6048
Step 15: 6048 + 432 = 6480
Step 16: 6480 + 432 = 6912
Step 17: 6912 + 432 = 7344
Step 18: 7344 + 432 = 7776
Step 19: 7776 + 432 = 8208
Step 20: 8208 + 432 = 8640
Step 21: 8640 + 432 = 9072
Step 22: 9072 + 432 = 9504
Step 23: 9504 + 432 = 9936
Step 24: 9936 + 432 = 10368
Step 25: 10368 + 432 = 10800
Step 26: 10800 + 432 = 11232
Step 27: 11232 + 432 = 11664
Step 28: 11664 + 432 = 12096
Step 29: 12096 + 432 = 12528
Step 30: 12528 + 432 = 12960
Step 31: 12960 + 432 = 13392
Step 32: 13392 + 432 = 13824
Step 33: 13824 + 432 = 14256
Step 34: 14256 + 432 = 14688
Step 35: 14688 + 432 = 15120
Step 36: 15120 + 432 = 15552
Step 37: 15552 + 432 = 15984
Step 38: 15984 + 432 = 16416
Step 39: 16416 + 432 = 16848
Step 40: 16848 + 432 = 17280
Step 41: 17280 + 432 = 17712
Step 42: 17712 + 432 = 18144
Step 43: 18144 + 432 = 18576
Step 44: 18576 + 432 = 19008
Step 45: 19008 + 432 = 19440
Step 46: 19440 + 432 = 19872
Step 47: 19872 + 432 = 20304
Step 48: 20304 + 432 = 20736
Step 49: 20736 + 432 = 21168
Step 50: 21168 + 432 = 21600
Step 51: 21600 + 432 = 22032
Step 52: 22032 + 432 = 22464
Step 53: 22464 + 432 = 22896
Step 54: 22896 + 432 = 23328
Step 55: 23328 + 432 = 23760
Step 56: 23760 + 432 = 24192
Step 57: 24192 + 432 = 24624
Step 58: 24624 + 432 = 25056
Step 59: 25056 + 432 = 25488
Step 60: 25488 + 432 = 25920
Step 61: 25920 + 432 = 26352
Step 62: 26352 + 432 = 26784
Step 63: 26784 + 432 = 27216
Step 64: 27216 + 432 = 27648
Step 65: 27648 + 432 = 28080
Step 66: 28080 + 432 = 28512
Step 67: 28512 + 432 = 28944
Step 68: 28944 + 432 = 29376
Step 69: 29376 + 432 = 29808
Step 70: 29808 + 432 = 30240
Step 71: 30240 + 432 = 30672
Step 72: 30672 + 432 = 31104
Step 73: 31104 + 432 = 31536
Step 74: 31536 + 432 = 31968
Step 75: 31968 + 432 = 32400
Step 76: 32400 + 432 = 32832
Step 77: 32832 + 432 = 33264
Step 78: 33264 + 432 = 33696
Step 79: 33696 + 432 = 34128
Step 80: 34128 + 432 = 34560
Step 81: 34560 + 432 = 34992
Step 82: 34992 + 432 = 35424
Step 83: 35424 + 432 = 35856
Step 84: 35856 + 432 = 36288
Step 85: 36288 + 432 = 36720
Step 86: 36720 + 432 = 37152
Step 87: 37152 + 432 = 37584
Step 88: 37584 + 432 = 38016
Step 89: 38016 + 432 = 38448
Step 90: 38448 + 432 = 38880

So, 432*90 = 38880