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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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