Arithmetic: Problem 2

Mary and her teacher went to explore a cave, and saw four equations written there on the wall:

8 x 8 = 8
9 x 9 x 9 = 5
9 x 3 = 3
(93 + 8) x 7 = 837

Her teacher said that their numbers may look like our numbers, but its values are different from ours. Their operations and symbols are the same as ours, though. For the people that lived in this cave, what is 89 x 57?

Please consider subscribing, here's our website: https://inquisitivekids.github.io