Question

What is the y-intercept of the graph of the line given by the equation 3y + 4x = 15?
A. 5
B. 4
C. 3
D. -4/3

Answer 1

Okay do you know what a y intercept is?

Answer 2

rewrite this eq in the form of:
x/a+y/b=1

Answer 3

yes

Answer 4

where a and b are the x and y intercepts resp.

Answer 5

Which number is on the y axes?

Answer 6

3

Answer 7

Okay. Then that is your answer. :)

Answer 8

really i would have never guessed that thanks gave you a medal

Answer 9

no thats not the answer

Answer 10

Then explain it?

Answer 11

wait that not the right answer then i am confused

Answer 12

first write the eq in the form i told u before

Answer 13

i did that but i dont see how that helps so please explain

Answer 14

what eq did u get can u write it here?

Answer 15

Sorry I am wrong. The wrong place to be sorry! I know this answer! I am so sorry @Gagecool I answered for the wrong person!

Answer 16

In this formula :

y tells us how far up the line goes
x tells us how far along
m is the Slope or Gradient i.e. how steep the line is
b is the Y-intercept i.e. where the line crosses the Y axis

The X and Y intercepts and the Slope are called the line properties. We shall now graph the line 3y-4x-15 = 0 and calculate its properties

Graph of a Straight Line :



Calculate the Y-Intercept :

Notice that when x = 0 the value of y is 5/1 so this line "cuts" the y axis at y= 5.00000

y-intercept = 15/3 = 5
Calculate the X-Intercept :

When y = 0 the value of x is 15/-4 Our line therefore "cuts" the x axis at x=-3.75000

x-intercept = 15/-4 = -3.75000
Calculate the Slope :

Slope is defined as the change in y divided by the change in x. We note that for x=0, the value of y is 5.000 and for x=2.000, the value of y is 7.667. So, for a change of 2.000 in x (The change in x is sometimes referred to as "RUN") we get a change of 7.667 - 5.000 = 2.667 in y. (The change in y is sometimes referred to as "RISE" and the Slope is m = RISE / RUN)

Slope = 2.667/2.000 = 1.333

Answer 17

oh thats okay

Answer 18

@Gagecool did u write it in that form?

Answer 19

first div by 15 on both sides

Answer 20

Here this goes to graph the strait line above!

Answer 21

4x + 3y = 15 that what i got by writing it like that i think that is right

Answer 22

Notice that when x = 0 the value of y is 5/1 so this line "cuts" the y axis at y= 5.00000

y-intercept = 15/3 = 5
Calculate the X-Intercept :

When y = 0 the value of x is 15/-4 Our line therefore "cuts" the x axis at x=-3.75000

x-intercept = 15/-4 = -3.75000
Calculate the Slope :

Slope is defined as the change in y divided by the change in x. We note that for x=0, the value of y is 5.000 and for x=2.000, the value of y is 7.667. So, for a change of 2.000 in x (The change in x is sometimes referred to as "RUN") we get a change of 7.667 - 5.000 = 2.667 in y. (The change in y is sometimes referred to as "RISE" and the Slope is m = RISE / RUN)

Slope = 2.667/2.000 = 1.333
Geometric figure: Straight Line

Slope = 2.667/2.000 = 1.333
x-intercept = 15/-4 = -3.75000
y-intercept = 15/3 = ?

Answer 23

Y-intercept equals?

Answer 24

no @Gagecool thats not it...can we go one step at a time?

Answer 25

Sorry to confuse you @Gagecool ! Hope this helps.

Answer 26

When i divide 15 on both sides i get 5 on one and 3.75 on the other what do i do next

Answer 27

correct!

Answer 28

that okay Qwertty123

Answer 29

@Gagecool thanks for understanding! :D

Answer 30

ya.. u get:
\[3y/15 + 4x/15=1\]

Answer 31

Now bring the coeffecient below 15 for both x and y

Answer 32

the answer comes out to be 5 when i divide then add

Answer 33

yes

Answer 34

Yes you are correct! Way to go @Gagecool

Answer 35

so the answer is 5

Answer 36

Yes you did it!!!

Answer 37

\[y/(15/3) + x/(15/4) =1\]

Answer 38

the denominator below y which is 5 (on reducing) is the y intercept

Answer 39

then thank you both for helping me out and giving me the answer 5.

Answer 40

the denominator below x is the x-intercept...Thats y i asked u to write in this form!

Answer 41

oh okay i see

Answer 42

You welcome @Gagecool !!!

Answer 43

if u r given such q's first write it in the above form...it will be very helpful!

Answer 44

welcome @Gagecool

Answer 45

@priyar you did a great job helping! I think you also deserve a medal! :D I will give you one! :)

Answer 46

thank u!

Answer 47

yeah i was able to give you both one

Answer 48

@Gagecool I will become your fan since I already gave my medal away.

Answer 49

well thank you, you think you can help me out on this next question

Answer 50

Um not sure... let me see the question :)

Answer 51

okay i will put it in the open question box above so get ready to see it

Answer 52

okay :D