SOLUTION: How do I solve using a system of two equations in two variables? The sum of the digits of a two-digit number is 9. The value of the number is 12 times the tens digit. Find the

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: How do I solve using a system of two equations in two variables? The sum of the digits of a two-digit number is 9. The value of the number is 12 times the tens digit. Find the      Log On


   

Question 141361This question is from textbook Prentice hall algebra 1
: How do I solve using a system of two equations in two variables?
The sum of the digits of a two-digit number is 9. The value of the number is 12 times the tens digit. Find the number.
I think the first equation is x+y=9 This question is from textbook Prentice hall algebra 1

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
X+Y=9
X=9-Y
10X+Y=12X
10(9-Y)+Y=12(9-Y)
90-10Y+Y=108-12Y
-10Y+1Y+12Y=108-90
3Y=18
Y=18/3
Y=6 ANSWER FOR THE UNITS DIGIT.
X=9-6
X=3
PROOF
36=12*3
36=36