Question

How would you find the equation of a line that is perpendicular to y = 3x + 1 and passes through point (1, -1)?

Answer 1

perpendicular means the slopes of the two lines are opposite reciprocals. Since the slope of y = 3x + 1 is "3", then the opposite reciprocal slope is
`(-1)/(3)`

Next, plug in the slope (
`(-1)/(3)` )and point (1, -1) into the point-slope formula: y - y₁ = m(x - x₁); where (x₁, y₁) is the point.

y - (-1) =
`(-1)/(3)`(x - 1)

y + 1 =
`(-1)/(3)`x +
`(1)/(3)`

y =
`(-1)/(3)`x +
`(-2)/(3)`