y=|x|-5

3x-1=6x+y

so confused. please help.

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- Jul 25th 2009, 08:02 PMsonatapleaseSolve and graph?
y=|x|-5

3x-1=6x+y

so confused. please help. - Jul 25th 2009, 08:12 PMVonNemo19
- Jul 25th 2009, 08:22 PMsonataplease
- Jul 25th 2009, 08:42 PMVonNemo19
Well, then, there is no way to "solve" these equations because there are two variables (x and y). But we CAN graph them.

If you look at my last post, you'll see that I "broke up" the first equation into two seperate equations. If you sketch the graph, it'll look like a v. - Jul 25th 2009, 08:50 PMsonataplease
- Jul 25th 2009, 09:21 PMVonNemo19
Solve for y:

$\displaystyle 3x-1=6x+y$

$\displaystyle 3x-6x-1=6x-6x+y$

$\displaystyle -3x-1=0+y$

$\displaystyle y=-3x-1$

You can see that this is a linear equation of the form $\displaystyle y=mx+b$, where $\displaystyle m=-3$ is the slope of the line, and $\displaystyle b=-1$ is the y-intercept.

You can use the y-intercept along with the slope of the line to sketch the graph. Or you could use the y-intercept along with another point (ie (1,-4)) to draw the graph. Either way is fine. - Jul 25th 2009, 09:30 PMsonataplease