Extra Credit System Of Equations

[mallorymal]

This is an extra credit problem that I want to do for my algebra 2 class but I'm not really sure how to start it.

Solve the following system of equations without using a graphing calculator.
You must show all algebraic steps to get full credit.

w+x+y+z = 2
2w-x-y+2z = 7
2w+3x+2y-z = -2
3w-2x-y-3z = -2

 

[royhaas]

Start by adding the first two equations.

 

[stapel]

I'm not really sure how to start it.

The only difference between a system of four equations in four unknowns and a system of three equations in three unknowns is the extra equation and the extra variable! :wink:

Everything else remains the same, so, just as there are various ways to approach a three-equation system, there are various ways to approach a four-equation system. The suggestion (above) is one. Others are equally valid. As long as you end up with a solution that works, your sequence of steps is no less valid than anybody else's. Don't worry about finding "the" right set of steps, because there isn't (only) one! :!:

So dig into this one, just like you've done the simpler ones. Don't doubt yourself. And have fun!

Eliz.