# Solve and graph?

• Jul 25th 2009, 08:02 PM
Solve and graph?
y=|x|-5
3x-1=6x+y

• Jul 25th 2009, 08:12 PM
VonNemo19
Quote:

Me too. Are trying to solve the system of the two equations. Or are you tryin to solve each independently?

This could help

$\displaystyle y=-x-5,$ $\displaystyle x\leq0$

$\displaystyle y=x-5$ $\displaystyle x>0$
• Jul 25th 2009, 08:22 PM
Quote:

Originally Posted by VonNemo19
Me too. Are trying to solve the system of the two equations. Or are you tryin to solve each independently?

This could help

$\displaystyle y=-x-5,$ $\displaystyle x\leq0$

$\displaystyle y=x-5$ $\displaystyle x>0$

sorry, shoulda specified... independently.

I am afraid I don't understand the equations you posted either. :( I am horrid at math.
• Jul 25th 2009, 08:42 PM
VonNemo19
Quote:

sorry, shoulda specified... independently.

I am afraid I don't understand the equations you posted either. :( I am horrid at math.

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 PM
Quote:

Originally Posted by VonNemo19
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.

I see... The second equation... how do I go about figuring that one? I graphed the first, did get a v. :D
• Jul 25th 2009, 09:21 PM
VonNemo19
Quote:

I see... The second equation... how do I go about figuring that one? I graphed the first, did get a v. :D

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 PM
Quote:

Originally Posted by VonNemo19
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.

(Clapping) THANK YOU!!!