You cannot.
Step-by-step explanation:
In order to solve for two variables, you need a system of equations, meaning at least two equations with the same two variables.
You cannot solve for x and y with just one equation as there will be an infinite range of solutions.
Let's say that there was a second equation, like:
x + 2y = 4
You could isolate the x (x = 4 - 2y), then substitute this value in the first equation:
3(4 - 2y) + 2y = 6
12 - 6y + 2y = 6 (expanded)
12 - 4y = 6
4y = 6
y = 6/4 = 3/2 (reduced)
Then, you plug this value of y into the x equation:
x = 4 - 2(3/2)
= 4 - 3
= 1
This is how you would solve it if you had another equation/a system of equations.
Hope this helps!
