One number is 10 times as large as another, and their difference is 81. find the numbers. if x represents the smaller number, than the larger number is wyzant

Let x be the smaller number:

smaller number = x

The other number is 10 times as large
⇒ larger number = 10x

Their difference is 81
⇒10x - x  = 81

Solve x:
10x - x = 81
9x = 81
x = 9

smaller number = x = 9
larger number = 10x = 10(9) = 90

The smaller number is 9 and the larger number is 90.