3x + 8y = 6
-4x -9y = -2
use substitution

Question

3x + 8y = 6
-4x -9y = -2
use substitution

anonymous · Answer

can someone help ?

anonymous · Answer

does anyone help on here or is it just a chat session ?

anonymous · Answer

Substitution means that you solve for one variable and then stick the resultant value back in for the other.

For example, we can the first equation for x
$$3x = 6 - 8y$$$$x = \frac{6 - 8y}{3}$$
Then put that in to the second one.
$$-4(\frac{6 - 8y}{3}) - 9y  = -2$$
Once you've got y, you can find x, of course.

anonymous · Answer

solve one of the lines for a single variable and then substitute that variable in the equation you haven't already solved for

anonymous · Answer

can you explain a little different , my instructor showed me a different way but cant find the paper that I wrote it down on

jusaquikie · Answer

solve one equation for x or y, let's use x, then substitute the equation you had for the answere for x in place of the x in the other equation and solve for y, once you have y as a number plug that in to either equation and solve for x

jusaquikie · Answer

SACAPUNTAS put it pretty clearly.

anonymous · Answer

Different how? It's really just as simple as solving one equation for one variable and putting what you find back into the other equation.

You could also solve for y, of course.
$$y = \frac{6 - 3x}{8}$$

Unless you mean a different method, but I thought we were talking about substitution. :D

anonymous · Answer

yes I was talking about substitution

jusaquikie · Answer

no, you are correct this is substitution method

anonymous · Answer

Ok. You know how to solve for a variable, right?

anonymous · Answer

thanks for the help I will figure it out on my own