C31b_Discussion_1_Response

** DATA_605_Discussion_1_C31_pg19_Daniel_Thonn Response **

http://rpubs.com/danthonn/354827

Format of equation: ax + b y + c*z = d

3x + 2y= 1 x - y = 2 4x + 2y = 2

Prepare Matrix:

M2 <- matrix(c(3,1,4,2,-1,2,1,2,2),3,3)
M2

##      [,1] [,2] [,3]
## [1,]    3    2    1
## [2,]    1   -1    2
## [3,]    4    2    2

Subtract 4row 1 from 3row 3

M2[3,] <- 3*M2[3,] -4*M2[1,] 
M2

##      [,1] [,2] [,3]
## [1,]    3    2    1
## [2,]    1   -1    2
## [3,]    0   -2    2

so, -2*y = 2 ; y = -1 ;

and

x - y = 2 ; x - (-1) = 2 ; x = 1 ;

Conclusion: x = 1 ; y = -1 ;

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