SOLUTION: Use matrices to solve the system of equations. 2x+4y=2 -3x+y=11

Algebra.Com
Question 1118042: Use matrices to solve the system of equations.
2x+4y=2
-3x+y=11
Answer by Alan3354(69443)   (Show Source): You can put this solution on YOUR website!
2x+4y=2
-3x+y=11
--------------------------

| 2   4   -2|
|-3   1  -11|

Det = 2*1 - (-3)*4 = 14
---
x*Det = 4*-11 + 1*2 = -42
x = -3
------
-y*Det = 2*-11 - 6 = -28
y = 2
=============
A different method, I think the method you mentioned.

| 2   4    2|
|-3   1   11|
---------------
| 1   2    1|  /2
|-6   2   22|  times 2
---------------  Subtract --> Row 1
| 7   0  -21|  /7
|-3   1   11|
---------------
| 1   0   -3|
|-3   1   11|
---------------
| 3   0   -9|  times 3
|-3   1   11|
--------------- Add --> row 2
| 1   0   -3|
| 0   1    2|

Same answers, the hard way.
RELATED QUESTIONS

Use matrices to solve the system of equations. 2x+y+2z=4 2x+2y =5 2x-... (answered by Edwin McCravy)
Use matrices to solve each system of equations. 11. 2x + y + z = 4 3x - y + 4z = 11 x -... (answered by TimothyLamb)
use matrices and Gauss-Jordan elimination to the solve the system of equations x-3y+z=2 (answered by TimothyLamb)
Use matrices to solve the system of equation. 3x+4y=-12... (answered by Fombitz)
Use matrices to solve the system of equation. 2x+y+3z= 3 -2x-y+z=5 4x-2y+2z=2 (answered by Fombitz)
Use matrices to solve each system of equations. If a system has no solution, so indicate. (answered by Edwin McCravy)
Use Matrices to solve system of equations: 2x+5y-3z=3 x+3y-2z=4 2x+y-3z=-6 (answered by Fombitz)
Solve the system of linear equation using inverse matrices. 2x-3y=-2... (answered by pie90010)
Use matrices to solve the system of equation. x+2y=-4... (answered by tommyt3rd)