Equation for the line

Question

Contains (3,-5) and is perpendicular to the line y=-8x+5.

Answer 1

The slope of y=-8x + 5 is -8

So the slope of the perpendicular line is (-1) / (-8) = 1/8

y = 1/8 x + b

x=3 y = 5 so 5 = 3/8 + b

40 = 3 + 8b

8b = 37

b = 37/8

so perpendicular line is y = (1/8) x + (37/8)