The slopes of 2 perpendicular lines with be reciprocals with the opposite sign. For example if you have the equation y=-5x+2, your slope is -5. In a line perpendicular to y=-5x+2, your slope would be 1/5. As for finding b in y=mx+b for your second equation, I would need more specific information.
Let be a random variable denoting the amount of winnings in any given round of the game. There is some probability of winning where , while , assuming these are the only two possible outcomes. So we have
