Thursday

July 24, 2014

July 24, 2014

Posted by **Kevin** on Thursday, February 26, 2009 at 8:31am.

5x+2y+z=-25

5x-3y-z=-23

3x+y+2z=-9

- algebra -
**Reiny**, Thursday, February 26, 2009 at 8:41amI would use elimination and start with the z's

Add the first plus the second to get

10x - y = -48

Double the second and add it to the third to get 13x - 5y = -55

ahhh, changed my mind, let's now switch to substitution

from above 10x - y = -48 or

y = 10x + 48

sub that into

13x - 5y = -55

13x - 5(10x + 48) = -55

etc. (I got x=5)

I am sure you can finish it from here.

- algebra -
**Kevin**, Thursday, February 26, 2009 at 8:57amI am coming up with (-5,-2,4) for my answer and I see you x=5

- algebra -
**Reiny**, Thursday, February 26, 2009 at 10:20amgood job

You can tell your answers are correct by merely subbing them back into the 3 original equations, they work

TRUST YOURSELF

**Related Questions**

Algebra - Solve the system of equation by graphing. Then classify the system. 3x...

Algebra 1 - What is an equation of a line perpendicular to the line with ...

Algebra Multiple Choice - Hello, This is the last of questions I have for my ...

Math- Algebra - hi wat method would i use and how would i solve this system of ...

Algebra - To solve the system of equations, which expression could be ...

Algebra - Show equation AX=B represents a linear system of two equations in two ...

algebra - my question is this how do you solve this equation? x=3y-1 x+2y=9 ...

ALGEBRA 1!PLZ HELP! - Use the Substitution method to solve the system of ...

math - Please explain in detail how to solve each question: At a certain high ...

Algebra II - 1. solve this system using matrices: 3.7x-2.3+4.2z=8 2.6+4.6y-3.9z=...