There are four types of slope: A positive slope means that the line is sloping upwards from left to right, meaning that as the x-coordinate increases, the y-coordinate also increases or Y is directly proportional to X. A negative slope means that the line is sloping downwards from left to right, meaning that as the x-coordinate increases, the y-coordinate decreases or Y is inversely proportional to X. A line with a slope of 0 is a horizontal line, meaning that the y-coordinate does not change as