Question 820352
4a + 7b = -30 
8a + 4c = -40 
6b + 4c = -20
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change to standard variable names x y z
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4x + 7y = -30 
8x + 4z = -40 
6y + 4z = -20
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copy and paste the above standard form equations in to this solver:
https://sooeet.com/math/system-of-linear-equations-solver.php
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answer:
x=a= -4
y=b= -2
z=c= -2
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Solve systems of linear equations up to 6-equations 6-variables:
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