Question

Which of the following lines is perpendicular to the line Y = 3x -4

Y= -3x+9
Y=1/3x -6
Y= 3x+ 1/4
Y= -1/3 x +4

Answer 1

D.

Explanation:

When a line is perpendicular to another, their slopes will be opposite reciprocal. For example, 1 would be -1, -3 would be
`(1)/(3)` , and
`(5)/(1)` would be -5. The equation is written in slope-intercept form:

`y=mx+b`

m is the slope, so find the equation with the opposite reciprocal of 3,
`-(1)/(3)`:

`y=-(1)/(3) x+4` is the only option with the correct slope, so the answer is D.