Final answer:
The equation of the boundary line of the graph 6x - 3y > 15 is y = 2x - 5.
Step-by-step explanation:
The equation of the boundary line of the graph of 6x - 3y > 15 can be found by rearranging the equation to solve for y. Start by subtracting 6x from both sides, which gives -3y > -6x + 15. Then divide both sides by -3 to isolate y, resulting in y < 2x - 5. So the equation of the boundary line is y = 2x - 5.