Find the solution using substitution method:
2x-y=2
2x+y=6

Graph this system of equations and solve:
2x-3y=-4
x+2y=5

Solve this system of equations using the elimination method:
x+3=y-3
2(x+3)=6-y

At a chocolate factory there are 900 bonbons packed in boxes with 6 and 12 units. How much boxes there are of each kind if there are 125 boxes?

Solve this system of equations graphically and algebraically:
2x-y=2
4x-2y=4