What is the answer to 4x-10y=12

4x - 10y = 12

2 (2x - 5y) = 12

2x - 5y = 12 / 2

2x - 5y = 6

This is the real answer.

Now,

if you want to find "x", it will be,

2x - 5y = 6

2x = 6 + 5y

x = (6 + 5y) / 2

And,

if you want to find "y", it will be,

2x - 5y = 6

5y = 2x - 6

y = (2x - 6) / 5