Question 94773
{{{(1/9)x-(1/5)y=20/9}}}
The first thing we want to do here is get rid of those annoying denominators.
Multiplying each term in the equation by 9*5 or 45, would do this, leaving us with:
5x - 9y = 5(20)
5x - 9y = 100
:
On this equation I assume you mean:
-10x + 18y = -200
:
Now it becomes apparent that this system cannot be solved. See what happens if
 we multiply the 1st equation by 2, and add to the 2nd equation:
:
 10x - 18y = 200
-10x + 18y = -200
------------------- adding eliminates everything!
 0x  +  0y = 0
:
This is just a form of "math student harassment" don't you think?