SOLUTION: 2x + 3y = 9 4x + 6y = 12 solve for x and y 2x = 9-3y x = (9/2)-(3y/2) 4((9/2)-(3y/2)) + 6y = 12 18-6y+6y=12 18=12 ???? what am I doing wrong? thanks

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: 2x + 3y = 9 4x + 6y = 12 solve for x and y 2x = 9-3y x = (9/2)-(3y/2) 4((9/2)-(3y/2)) + 6y = 12 18-6y+6y=12 18=12 ???? what am I doing wrong? thanks       Log On


   



Question 105806: 2x + 3y = 9
4x + 6y = 12
solve for x and y
2x = 9-3y
x = (9/2)-(3y/2)
4((9/2)-(3y/2)) + 6y = 12
18-6y+6y=12
18=12 ????
what am I doing wrong?
thanks

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
You're not doing anything wrong.
When you solve and get an answer like that.
18=12
that means that there are no x,y that make these equations true.
In other words, there is no solution. if
you look at the equations you can see why.
1.2x+%2B+3y+=+9
2.4x+%2B+6y+=+12
If I multiply the first equation by 2, I get the left hand side of the second equation but not the right hand side.
1.4x%2B+6y+=+18
2.4x+%2B+6y+=+12
These equations are inconsistent.
Its like saying A=C and B=C, but A does not equal B.
It doesn't make sense.
You're correct in your derivation. No solution.