Geometry Find the equation of the line for each situation.
a line with a y - intercept of 4 and a slope of -1
a line passing through the point (3, 4) and having a slope of -2
a line passing through the points (1, -1) and (9, 3)

Find the equation of a line with each of the following characteristics.
parallel to the line y = 3x + 5 and has a y-intercept of -1
perpendicular to the line y = 5x - 1 and passes through the point (10, 8)
perpendicular to the line y = 1⁄3x + 4 and has an x-intercept of 2.