EXPLANATION
Given the equation y= -1.5x + 3
In order to get a system with just one solution, the viable options are those that allow both lines to intersect in just one point.
Those equations are:
y= -1.5x
y=-2x + 3
The system of equations y=-1.5x+3 and y=-1.5x+6 has no solution because subtracting both expressions give us the result 3=0
The system y=-1.5x+3 and 2y = -3x+6, or in the same way the system y=-1.5x+3 and 2y + 3x = 6 has no solution because they have the same expression.
