How do you find the X,Y,and the Z for algebra II?

Question

2X+5y+2z=-5

-3x+3y+5z=2

x+4y-z=3

please help me I'm so confused

Answer 1

The way to do this is to find what one variable would be first:

Take the 3rd equation (x = -4y + z + 3)

Substitute '-4y + z + 3' in the other two equations for all x

2(-4y + z + 3) + 5y + 2z = 5

-3(-4y + z + 3) + 3y + 5z = 2

Keep going from there

Answer 2

Many, many different ways, including matrix manipulation, Gaussian elimination, Cramer's rule etc.

Here's a link that should help you:

http://en.wikipedia.org/wiki/Gausian_eli...