use gaussian elimination to solve the following system of equation:(adsbygoogle = window.adsbygoogle || []).push({});

2x + y - 3z = 3

4x - y + 2z = 25

-3x + 2y + 4z = -9

ok so first i rearranged them so the inital numbers were in decending order (for the pivot)

R1 -> 4x - y + 2z = 25

R2 -> -3x + 2y + 4z = -9

R3 -> 2x + y - 3z = 3

pivot factor r = -3/4 for R2

pivot factor r = 1/2 for R3

R1 = 4x - y + 2z = 25

R2 + (3/4)R1 = (-3x+(3/4)4x) + (2y + (-3/4y)) + (4z + (3/4)2z) = -9 + (3/4)25

= 0x + 1.25y + 5.5z = 9.75

R3 = (2x - 1/2x) + (y +1/2y) + (-3z-z) = 3 - 25/2

= 0x + 1.5y - 4z = -9.5

now solve for R2 and R3 to find Z

pivoting factor r = 1.25/1.5 = 5/6

R2 - 5/6R3 = (1.25y - 5/6(1.5y)) + (5.5z - 5/6(4z)) = 9.75 - 5/6(9.5)

= 0y + ((33/6)z - (20/6)z) = 58.5/6 - 47.5/6

= (13/6)z = 11/6

z = 11/13

and i know thats wrong...can anyone point out where i've went wrong?

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# Homework Help: Gaussian Elemination

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