plans for a stadium are drawn on a coordinate grid. one wall lies on the line y=2x+3. a perpendicular wall passes through the point (4, -7). write the equation of the line that contains the new wall

Question

solomonzelman · Answer

just gave you that link...

abbie · Answer

y=-1/2x-5
y=2x-15
y=1/2x-9
y=-2x+1

solomonzelman · Answer

how do you find a perpendicular slope?

abbie · Answer

idk

abbie · Answer

im watching a khan academy video though maybe it could help

solomonzelman · Answer

I can help explain this right now in a short simple phrase.

abbie · Answer

go on then

solomonzelman · Answer

multiplicative inverse of the slope then times '-1'  is your perpendicular slope.

solomonzelman · Answer

@abbie, see? So what is the slope going to be?

solomonzelman · Answer

for a slope a it is  -1/a

abbie · Answer

ok

solomonzelman · Answer

so if for A the slope is -1/A, for 2 the slope is _

abbie · Answer

um 1/2?

solomonzelman · Answer

close, (it is multiplicative inverse, and then times -1)

abbie · Answer

-2?

solomonzelman · Answer

you got the 1/2 part right, but think one more time....

abbie · Answer

-1/2

solomonzelman · Answer

Yup! Bingo!

abbie · Answer

lol ok

solomonzelman · Answer

K, so lets graph the line y=2x+3.

Plug in -1  &  1  for x and connect the points that you get with a strait line.

solomonzelman · Answer

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solomonzelman · Answer

now graph the same but add the point  (4, -7) to the graph.
(don't connect it to the line yet, just do the same graph as mine and draw this additional point.)

abbie · Answer

Im having a headache right now I think Ill do it later

solomonzelman · Answer

|dw:1383375856706:dw|

I graphed this on a paper.