Manipulating systems of equations

Maths

x+y=3 AND 2x-y=5 This pair of equations has been transformed.  Which of the following are equivalent to the original pair?

x+y=3 AND 2x-y=5 This pair of equations has been transformed. Which of the following are equivalent to the original pair?

2x+5y=9 AND 5x+4y=14. Solve the simultaneous equations.

10x+5y=5 AND 3x-5y=34. Solve the simultaneous equations.

3x+2y=5 AND 3x-2y=7.  If I add these two equations together, which unknown will be eliminated?

3x+2y=5 AND 3x-2y=7. If I subtract the two equations, which unknown will be eliminated?

3x-5y=17 AND 2x-5y=10. Subtract the first equation from the second equation.

2x-5y=10 AND 3x-5y=17. Add the two equations together.

3x-5y=17 AND 7x-5y=20. How can I eliminate y from these simultaneous equations?