The line y = (5/4)x - 1 has slope 5/4
Any line perpendicular to the given line has slope -1/(5/4) = -4/5
Equation of line with slope -4/5 and containing the point (4,5):
y - 5 = (-4/5)(x - 4)
y = (-4/5)x + 41/5 or 4x + 5y = 41
Ess C.
10/06/17