Question 854257
2z-5w=-5, 
 6w+7z=10
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5w - 2z = 5
6w + 7z = 10
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|5 -2 -5|
|6 +7 -10|
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Det = 5*7 - 6*-2 = 47
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w*Det:
|-2 -5|
|7-10|
= 20 + 35 = 55
w = 55/47
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-z*Det:
|5 -5|
|6 -10|
= -50 + 30 = -20
z = 20/47