Question

5x-4y+6=0 solve for y and find the slope. please show work, trying to figure out what i'm doing wrong.

Answer 1

put it in the form y=mx+b

Answer 2

m is the slope

Answer 3

-4y=-5x-6. Getting y by itself.
Y= -5/-4x-6/-4. Getting y by itself
y=5/4x+3/2. Simplified.
Slope is 5/4. Yintercept is 3/2

Answer 4

Right. You're working for slope intercept form. y=mx+b

Answer 5

DSS thank you very much

Answer 6

So in other words we multiply the negative fractions times -1?

Answer 7

A negative divided by a negative is a positive. -5/-4 = 5/4

Answer 8

-6/-4 negative divided by negative is positive. 3/2. I think I missed typed part of my process

Answer 9

no, I didn't. It justlooked confusing.

Answer 10

Ok, so we treat every fraction as a division problem?

I have another question how would you solve for y and x and the slope for 8(x+10y)=4

Answer 11

distribute through the parenthesis

Answer 12

I did however the answers i'm inputting are not correct you get 8x+80y=4 you turn it into y=mx+b format and you get 80y=-8x+4 which would in turn give you y=10x+20 correct?

Answer 13

80y = -8x + 4 (now divide by 80)
y = -8/80x + 4/80
y = - 1/10x + 1/20

Answer 14

oh I see what I did wrong, I divided the denominator by the top number. thanks!

Answer 15

so the slope is -1/10

do you need to find the x and y intercept ?

Answer 16

yeah
I do

Answer 17

question if I divided by 8 on the 8/80 I don't need to do it to the other fraction correct I can divide by 4?

Answer 18

to find the y intercept, sub in 0 for x
8x + 80y = 4
8(0) + 80y = 4
80y = 4
y = 4/80
y = 1/20

to find the x intercept, sub in 0 for y
8x + 80y = 4
8x + 80(0) = 4
8x = 4
x = 1/2

understand ?

Answer 19

yes, you can divide by 4, you do not need to divide by 8

Answer 20

yes because we simplify after we divide. Thanks that makes a lot more sense then what the book explains. and to solve for x and y there is no need to put it into y=mx+b form correct?

Answer 21

not really, unless you are looking for just the y intercept, because in y = mx + b, the y intercept is in the b position

Answer 22

or if you are looking for the slope, it is in the m position

Answer 23

oh ok, so with fractions do you a similar process, so for example a -5/3 x -7/4 y= 5

Answer 24

if you wanted to work this problem out without the fraction, multiply the equation by the common denominator, which is 12.
-5/3x - 7/4y = 5 (multiply by 12)
-20x - 21y = 60
now put it in y = mx + b
-21y = 20x + 60
multiply by -1 to make x positive
21y = -20x - 60
divide by 21
y = -20/21x - 60/21
y = -20/21x - 20/7

or you can work with the fractions...
-5/3x - 7/4y = 5
-7/4y = 5/3x + 5
y = (5/3x) / (-7/4) + (5)/(-7/4)
y = 5/3x * -4/7 + 5 * - 4/7
y = - 20/21x - 20/7

either way, you will get the same answer

Answer 25

any questions ?

Answer 26

So whenever dividing a fraction you flip and multiply it?

Answer 27

yes

Answer 28

So the slope is -20/21 ?

Answer 29

yes

Answer 30

and the y intercept is -20/7

Answer 31

oh okay
so I just tried doing the x intercept and lost myself again

Answer 32

sub in 0 for y

Answer 33

so I get 20/21x=-20/7 correct?

Answer 34

and now divide 20/21x by -20/7? which would turn into 21/20 * -20/7?

Answer 35

yes

Answer 36

yes
20/21x = -20/7
now divide by 20/21
x = (-20/7)/(20/21)
x = -20/7 * 21/20

Answer 37

you flip what you are dividing by

Answer 38

and you get 420/140 and we simplify it correct?

Answer 39

which leaves me with 3?

Answer 40

don't forget about the sign
-420/140 reduces to - 21/7 = -3

Answer 41

Oh that's right forgot about the negative. Thank you very much! is there a way I can add you I'm starting my business major so if I have any further questions if you could possibly be of more help?

Answer 42

yes you can add me

Answer 43

I don't know how.

Answer 44

click on my name and it will take you to my page and just click become a fan

Answer 45

Got it thanks! have a great sunday.

Answer 46

you too :)