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Question 384149: I am really having a hard time with finding intercepts to a problem so I can graph it. I am having a hard time following what numbers to put where to find the x and y intercepts. my problem I have to slove and graph is 3x-4=12. Is there an easy way to find these intercepts. I am 59 yrs old and never took algebra before, and now I am in college algebra and really need some help. Any help to make the steps easier to find the x and y intercepts would be appreciated.
Thank you
Millie Ives
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Perhaps the problem should be
3x - 4y = 12.
Put it in the slope/intercept form which is y = mx + b, where m=slope, b=y intercept
subtract 3x from both sides
-4y = -3x + 12
y has to be positive, multiply both sides by -1
4y = +3x - 12
The coefficient of y has to be 1, divide both sides by 4
y = x - 
y = x - 3
:
the y intercept occurs when x=0, replace x with 0, and find y
y = (0) - 3
y = 0 - 3
y = -3, is the y intercept
The ordered pair to graph this; x=0, y=-3
:
The x intercept occurs when y = 0, write it like this, and solve for x
x - 3 = 0; (replacing y with 0)
Add 3 to both sides
x = +3
multiply both sides by 4, to get rid of the fraction
3x = 4(3)
3x = 12
Divide both sides by 3
x = 
x = 4; is the x intercept
the ordered pair to graph this: x=4, y=0
:
Graphically it should be apparent

You can see the line intercepts the y axis at -3
and the x axis at +4
:
:
How about it, did this shed some lite on this "intercept stuff" for you?
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