y - y1 = m(x - 1) slope(m) = 1/4 (5,5)...x1 = 5 and y1 = 5 now we sub y - 5 = 1/4(x - 5) <==== ur parallel line ================== perpendiculr lines will have a negative reciprocal slope. To find the negative reciprocal, u flip the number and change the sign. So the negative reciprocal of 1/4 is -4....see how I flipped 1/4 and made it 4/1...then changed the sign making it -4/1 or just -4. That will be ur slope of the perpendicular line.
y - y1 = m(x - x1) slope(m) = -4 (5,5)...x1 = 5 and y1 = 5 now we sub y - 5 = -4(x - 5) <=== ur perpendicular line
