Write an equation of the line perpendicular to the given line that contains P.

y space equals space 1 fifth x space plus space 1; P(2, -7)

Question

Write an equation of the line perpendicular to the given line that contains P.

y space equals space 1 fifth x space plus space 1; P(2, -7)

anonymous · Answer

help me pleaase!!!

irishboy123 · Answer

lmLtfy!

"y space equals space 1 fifth x space plus space 1" is:

$y = \frac{1}{5}x+ 1$

and hint: if the lines $y = mx + c$ and $y = m' x + c'$ are perp,  then $m' = -\frac{1}{m}$ 

and $m = -\frac{1}{m'}$

anonymous · Answer

im osrry i still dont understand

irishboy123 · Answer

what is the gradient of your line?

anonymous · Answer

there is no line

anonymous · Answer

is the answer y=-1/5x-33/5??

irishboy123 · Answer

go back to your question

you have a line

irishboy123 · Answer

i did the Latex for you

irishboy123 · Answer

no

m = -1 / m'

m is slope of original line

m' is slope of line that is perp to original line

anonymous · Answer

oh right so then would it be y=1/5x+3

irishboy123 · Answer

i will keep asking this :p

what is the slope of your original line, the one that you posted??

irishboy123 · Answer

do you know what a slope is?

$\frac{rise}{run}$  ??

anonymous · Answer

1/5?

irishboy123 · Answer

great

so m' = -1 / m

m is slope of original line

m' is slope of line that is perp to original line

anonymous · Answer

so then it would be -1/5?

irishboy123 · Answer

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irishboy123 · Answer

you're just "minusing" it.  you need to invert and minus it