First, you have to simplfy your equations, 2x+3y=3. Subtract 2x from both sides, get 3y=-2x+3. Divide each side by 3, get y=-2/3x+1.
Simplify your other equation, 2y=3x-4. Divide each side by 2, get y=3/2x-2.
Now you have your 2 equations, y=-2/3x+1, and y=3/2x-2. These lines are perpendicular if you make a graph and plot the lines.