Question

I am studying for a test tomorrow and i would greatly appreciate it if someone would help me find the y intercept of 3y=15x-9

Answer 1

To find the y-intercept, you plug in x = 0 and solve for y


3y=15x-9

3y=15(0)-9 ... replace x with 0

3y = 0 - 9

3y = -9

y = ???

Answer 2

Thank you

Answer 3

what did you get for y?

Answer 4

Well, if i read your equation right it is -9

Answer 5

3y = -9

but we want to know what y is (not 3y)

Answer 6

if 3 times y = -9, then y = ???

Answer 7

-3

Answer 8

So the. What would 2x+8y=12

Answer 9

Then*

Answer 10

good, the y-intercept is -3 which means the graph crosses the y axis at the point (0,-3)

Answer 11

to find the y-intercept of 2x+8y=12, you plug in x = 0 and solve for y

2x+8y=12

2(0)+8y=12

...
...
...

y = ???

Answer 12

6

Answer 13

no

Answer 14

that's the x-intercept actually

Answer 15

because plugging in y = 0 gives you

2x+8y=12

2x+8(0)=12

2x = 12

x = 12/2

x = 6

Answer 16

I am sosorry, you are right, i looked badly

Answer 17

that's ok

Answer 18

So then the y intercept would be 8

Answer 19

no

Answer 20

if 8y = 12, then y = ???

Answer 21

hopefully you see how I'm getting 8y = 12

Answer 22

No

Answer 23

I plugged in x = 0 into 2x+8y=12

Answer 24

2x+8y=12

2(0)+8y=12

0 + 8y = 12

8y = 12

Answer 25

Yes, i get that already, but the thing is how can you grab 8 times y equals 12

Answer 26

8y means "8 times y"

Answer 27

what undoes multiplication?

Answer 28

So the oppposite of multiplication

Answer 29

Or just minus

Answer 30

no, division actually

Answer 31

you divide both sides by 8 to completely isolate y

Answer 32

Because the oppposite is divsion

Answer 33

yes, division undoes multiplication (by definition)

Answer 34

So we end up with?

Answer 35

you tell me

Answer 36

8y = 12

divide both sides by 8

Answer 37

How do i do that, 8(8y=12)

Answer 38

Like that?

Answer 39

8y/8 turns into 1y/1 or just y on the left side

Answer 40

12/8 = ???

Answer 41

1.5

Answer 42

or 3/2

Answer 43

the y-intercept is 3/2 or 1.5

Answer 44

Does the slash mean division for you people

Answer 45

"you people"?

Answer 46

sounds a bit rude

Answer 47

You guys

Answer 48

but yeah, / means division

Answer 49

2/3 means "2 divided by 3" and it's also fraction notation

Answer 50

Are you a teacher by any chance

Answer 51

not yet, but I'm on my way to becoming one

Answer 52

Thats great, keep on it

Answer 53

thanks

Answer 54

Bye

Answer 55

bye