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bignick79 June 15th, 2010 09:44 AM

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

The Chaz June 15th, 2010 10:15 AM

Re: quick q
 
The slope and y intercept are most easily identified when the equation is in "slope intercept form"
y=mx + b

mfetch22 June 15th, 2010 10:25 AM

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.

soroban June 15th, 2010 10:41 AM

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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