Write an equation of the line passing through point P that is perpendicular to the given line. P(−1,−2), y=−4x+13

Answer 1

slope of perpendicular line = negative inverse of the x coefficient = 1/4

y= x/4 + b where b = y intercept. Just plug in y=-2, x=-1 and solve for b

-2 = -1/4 + b

b = -2 + 1/4 = -7/4

equation of the perpendicular is

y= x/4 -7/4 or

4y = x -7 or

x-4y = 7

the 13 in the original equation is irrelevant. It could have been any real number