If {4x-3y=17 and 2x-5y=-11 then y=?

You need to solve this "system of linear equations."  In other words, find a point (x,y) that satisfies both 4x-3y=17 and 2x-5y=-11.

Try solution by elimination.  Multiply the 2nd equation by -2 to obtain -4x+5y=22.  Add this result to the 1st equation.  I'd suggest you write this out to see what is happening.  

 4x-3y=17

-4x+10y=22

        7y=39.  Solving for y, we get y=39/7 (a rather awkward fraction).

Now find x.  To do this, substitute 39/7 for y in either of the given equations.  Solve the resulting equation for x.

Write your solution in the form (x, y):  ( ? , 39/7).