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gjhfdfg
 2 years ago
Gaussian elimination method help?
gjhfdfg
 2 years ago
Gaussian elimination method help?

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gjhfdfg
 2 years ago
Best ResponseYou've already chosen the best response.0I have absolutely know idea how to solve this problem using it, 3x  2y + 2z  w = 2 4x + y + z + 6w = 8 3x + 2y  2z + w = 5 5x + 3z  2w = 1 Wants me to find the solution

gjhfdfg
 2 years ago
Best ResponseYou've already chosen the best response.0I mean no instead of know. *face palm*

tyteen4a03
 2 years ago
Best ResponseYou've already chosen the best response.1The matrix version or the simple "moving variables around" version?

gjhfdfg
 2 years ago
Best ResponseYou've already chosen the best response.0I believe its the 'simple' moving variables around version

tyteen4a03
 2 years ago
Best ResponseYou've already chosen the best response.1I just threw this into WolframAlpha, and it didn't give me any value results. Do you need value results?

gjhfdfg
 2 years ago
Best ResponseYou've already chosen the best response.0Nope, it says find the solution or state that none exists./ So I guess there isnt a solution

tyteen4a03
 2 years ago
Best ResponseYou've already chosen the best response.1Oh, then I'll show you why there isn't one then. When doing the simple version of Gaussian elimination, always look for "bare" variables first (variables that has a coefficient of 1, otherwise known as "that variable with no numbers"). In this case: 3x  2y + 2z  w = 2 (1) 4x + y + z + 6w = 8 (2) 3x + 2y  2z + w = 5 (3) 5x + 3z  2w = 1 (4) In this case, we notice that in Equation 1 and 3, both w are bare (although there's a minus sign before the w in Eq. 1). Shift w around in Eq. 1 to make it positive again. Now change the subject: 3x  2y + 2z  w = 2 becomes w = 3x  2y + 2z  2 and 3x + 2y  2z + w = 5 becomes w = 5 + 3x  2y + 2z. Now that w is (sort of) found, hook them together: 3x  2y + 2z  2 = 5 + 3x  2y + 2z. You see that after simplifying you're left with 2 = 5, which is obviously impossible. Therefore, there is no solution since two of the socalled "related equations" contradict each other.
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