0.25x + 0.5y = 4
12 = 12x - 3y
2y -10 = 18x
y = 6x + 4
y = 11x - 7
y - 7x = 14
7y - 21x - 9 = 0
16y + 2x = 9
y = 10x
3y - 15x = 9
12y = 36x + 3
3y = 27x + 11
6y + x = 12
2y = 14x - 12
7y = 56x + 49
4y -8 = 44x
2y = 4x + 8
4y + x = 8
6y - 30x + 12 = 0
10y = 90 - x
