Question

Write the equation of the line that is perpendicular to the given line and that passes through the given point.
y + 2 = 1/3(x - 5); (-4, 3)

a) y = -3x + 15
b) y = -3x - 9
c) y = -4x + 3
d) y = -1/3x - 11

Answer 1

Since your slope is \(\sf \color{}{\frac{1}{3}}\), that means the perpendicular slope, the one you want, is 3. The equation of a line is in the form: \(\sf \color{limegreen}{y=mx+b}\)

Answer 2

Plug in the given points and your slope, and solve for \(\sf \color{red}{b}\)

Answer 3

That means \(\sf \color{blue}{3=-3(-4)+b}\)

Answer 4

the perpendicular slope is -3

Answer 5

Opposite reciprocal of the original slope.

Answer 6

Then, plug it in for \(b\). And you should get: y=-3x+\(\sf \color{blue}{b}\)

Answer 7

then use point slope form which is \[y-y1=m(x-x1)\]

Answer 8

so it would be a? (:

Answer 9

using your given points and the perpendicular slope of -3, the equation to solve is as followed
\[y-3=-3(x+4)\]

Answer 10

put into slope intercept form
\[y=mx+b\]

Answer 11

@abb0t it is A, correct?

Answer 12

It is B.

Answer 13

Not quite. What's 3-12?

Answer 14

-9

Answer 15

the same as 12-3 times negative 1

Answer 16

So, \(\sf \color{red}{b=-9}\)

Answer 17

A perpendicular line has a slope that is the opposite reciprocal of the original. you flip AND change the sign!

Answer 18

y=mx+b
(x,y)=(-4,3) and m=1/3
3=3(-4)+b
3=-12+b
b=-9

so y = -3x - 9

Answer 19

Correct

Answer 20

Why are you yelling @Westfallcw