The tens digit of a number is twice the ones digit. the sum of the digits in the number is 12. what is the number?

choose what the expressions below best represent within the context of the word problem.

Let x = the ones digit
Let y = the tens digit

x+2y=12
x=2y
x+y=12 substitute x for 2y to get:
(2y)+y=12 add like terms to get:
3y=12
3y=12 divide both sides by 3 to get:
y=4
x+y=12 substitute y for 4 to get:
x+4=12 subtract 4 from both sides to get:
x=8
so if x=ones
and y=tens
then the answer is 48