What is the equation of the line that passes through the given point and is perpendicular to the given line? Point: (1,1) Line: y=1/5x+4/5

Question

a) y=-5x+6

b) y=-5x+4/5

c) y=-5x-5/4

Answer 1

Hello Judite!

The line presented has equation

y = (1/5)x + 4/5

Note that the slope of this line is 1/5. The slope of the perpendicular line is the reciprocal opposite, which is -5

The perpendicular line has the form:

y = -5x + b

If it passes through (1,1), the (1,1) must satisfy the equation.

1 = -5*1 + b

b = 6

y = -5x + 6

The answer is A