The system of equation have no solution if lines are parallel to each other. The parallel have equal slope but different y-intercept.
The slope of line y = -2x + 3/2 is -2. So the equation y = mx + b has also slope of -2, means m = -2.
The value of y-intercept b can take any value as parallel lines have equal slope but uneqyal intercept. So from the options possible values of b are -1/3 and -2/3.
Thus correct options are,
m = -2 and b = -1/3
m = -2 and b = -2/3