y = -3x + 6
y = x + 2
-3x + 6 = x + 2
6 - 2 = x + 3x
4 = 4x
x = 1
y = -3(1) + 6 = -3 + 6 = 3
x = 1 and y = 3 ==> This has one solution
y = 2x + 6
y = 2x -1
2x + 6 = 2x -1
6 = -1 ====>> This is false, therefore no solution
y = -x + 4
2y = -2x + 8 ==> y = -x + 4
-x + 4 = -x + 4 ==> This is true for any value of x, so it has an infinite numbr of solutions