From the second equation, y=3x-11, so we substitute this value for y into the other equation: 4x-5(3x-11)=13. That is, 4x-15x+55=13, -11x+55=13. Add 11x to each side: 55=13+11x, and subtract 13 from each side: 42=11x so 42/11=x or x=42/11. Therefore y=3*42/11-11=126/11-11=11 5/11 - 11=5/11. Check this out by substituting for x and y in 4x-5y and we get 168/11-25/11=143/11=13.