Answer :
You need more information than that to solve for x and y. However, it is possible for you to graph the equation and see what all the possible values for x and y can be. A possible coordinate can be x=3 and y=3.
I'm not sure what you need to solve for, so I'll solve for both x and y.
3x + 6y = 27
3x = 27 - 6y
x = (27 - 6y)/3
x = 9 - 2y
so there's x
3x + 6y = 27
6y = 27 - 3x
y = (27 - 3x)/6
y = 4.5 - .5x
And there's y
3x + 6y = 27
3x = 27 - 6y
x = (27 - 6y)/3
x = 9 - 2y
so there's x
3x + 6y = 27
6y = 27 - 3x
y = (27 - 3x)/6
y = 4.5 - .5x
And there's y