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June 15th, 2010, 09:44 AM   #1
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quick q

given 2x+3y=12, what is the slope, y intercept, and what would the graph look like

is the slope??? m= -3
y int: b= 6

any help?

thanks
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June 15th, 2010, 10:15 AM   #2
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Re: quick q

The slope and y intercept are most easily identified when the equation is in "slope intercept form"
y=mx + b
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June 15th, 2010, 10:25 AM   #3
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Re: quick q

Quote:
Originally Posted by bignick79
given 2x+3y=12, what is the slope, y intercept, and what would the graph look like

is the slope??? m= -3
y int: b= 6

any help?

thanks
Remeber, if you can get a linear equation like this one into the following form:



Then you know the y-intercept and the slope.




So, we have the equation:



Subtracting 2x from both sides gives:



Then dividing both sides (meaning the whole of both sides) by 3 gives:



this becomes, by basic rules of fractions, the following:



This is in the form:



So,



and



This graph would look like a line, slanted from top left to bottom right, intersecting the y-axis at four. Basically draw a point at (0, 4) and move down two [-2 in the slope, m] and to the right 3 [+3 in the slope, m] to find your next point. Continue this to get a picture of the graph, in both directions. Hope this helps, anymore questions post them here and I'll try to clarify.
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June 15th, 2010, 10:41 AM   #4
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Re: quick q

Hello, bignick79!

Quote:
Given:[color=beige] .[/color]

What is the slope, y-intercept, and what would the graph look like?

Get the equation into the form:[color=beige] .[/color]
[color=beige]. . [/color]That is, solve for



[color=beige]. . . [/color]

[color=beige]. .[/color]
[color=beige]. . . . . . . . . . . . . . . . . . [/color][color=beige] - - [/color]
[color=beige]. . . . . . . . . . . . . . . . [/color]slope[color=beige] . [/color]y-intercept


~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~


This line has a y-intercept at






[color=beige]. . [/color]

Code:
        |
*       |
    *   |4        +3
        o - - - - - - - - - +
        |   *               :
        |       *           : -2
        |           *       :
        |               *   :
        |                   o
  - - - + - - - - - - - - - - - * - - - 
        |                           *
        |
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