...what is the slope of the line that passes through points (-2, -1) and (5, 6)
what is the slope of the line that passes through points (2, 4) and (-3, 4)
for the first two ...
are the lines 2x + 5y = 1 and y = 5/2x + 4 parallel, perp, neither, or the same
parallel lines have the same slope, perpendicular lines have slopes that are opposite reciprocals ... not parallel or perpendicular would be neither