Question

Find the equation of a line that passes through the point (4,2) that is perpendicular to the line y = 4/3 x. Show your work.

Answer 1

you know the slope of
\[y=\frac{4}{3}x\]?

Answer 2

No, I am confused on the whole thing.

Answer 3

hint
it is the only number you see

Answer 4

satellite after this question can u plz come look at mine

Answer 5

k

Answer 6

thanks

Answer 7

I am confused because i need the work draw out so i can answer on paper.

Answer 8

and i never worked with perpendicular piles

Answer 9

forget about perpendicular for a moment
step one is to find (with your eyeballs) the slope of
\[y=\frac{4}{3}x\] which is pretty much the only number you are looking at

Answer 10

all i was told is to flip it.

Answer 11

can we take this one step at a time?

Answer 12

yes but my teacher all he said was get the slope and flip it. And i cant work it out.

Answer 13

forget what your teacher said
it is wrong in any case
we need first to find the "it"
i.e. we need to find the slope of
\[y=\frac{4}{3}x\] can you please write the slope?

Answer 14

thats my problem, I can only do slope of two points.

Answer 15

oh i see
you find the slope if you are told two points by computing it
but here you are not told two points, you are told the equation of the line
therefore you are also told the slope
it is the only number you see there

Answer 16

if you have
\[y=mx+b\] the slope is \(m\) and the \(y\) intercept is \(b\)
you have
\[y=\frac{4}{3}x\] what is \(m\) in this example?

Answer 17

.... 4/3 ?

Answer 18

\[\huge \text{whew!!}\]

Answer 19

how would it go from there.... to make the equation.

Answer 20

ok now we have step one, find the slope which really means just write it since there is nothing to find
now on to step two

Answer 21

for the slope of the "perpendicular line" you have to do two things
take your slope (which we now know is \(\frac{4}{3}\) and
a) flip it
b) change the sign

the slope of your perpendicular line is therefore
\[-\large \frac{3}{4}\]

Answer 22

so the equation would be y=-3/4x + b ?

Answer 23

right that is it
you need \(b\) and there are two ways to find it

Answer 24

the point is \( (4,2)\) and the slope is \(-\frac{3}{4}\) use the point slope formula and write
\[y-2=-\frac{3}{4}(x-4)\] and solve for \(y\) is one way

Answer 25

dont you distribute the -3/4...? Cause that's where i get lost.

Answer 26

yes you do

Answer 27

\[y-2=-\frac{3}{4}x+3\] is the first step

Answer 28

because \(-\frac{3}{4}\times -4=3\)

Answer 29

last step is to add \(2\) and get
\[y=-\frac{3}{4}x+5\]

Answer 30

where does the minus 4 come from