When 2 lines are perpendicular, their slopes are negative reciprocals of one another.
Start by finding the slope of the line whose equation is given: -2y=3x+7.
Dividing both sides by -2, y = -(3/2)x - 7/2
The slope of any line perpendicular to this line is the neg. recipr. of -3/2. This comes out to +2/3.
This is the answer.