Выразить x1)[tex] fraca times bc + d = x times b

( ab / c ) + d = xb - c 
( ab + dc ) / c = xb - c 
xb = ( ( ab + dc ) / c ) + c 
xb = ( ab + dc + c^2 ) / c 
x = ( ( ab + dc + c^2 ) / c ) : b 
x = ( ab + dc + c^2 ) / bc 
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ab + d = b( x - c ) 
x - c = ( ab + d ) / b 
x = ( ( ab + d ) / b ) + c 
x = ( ab + d + cb ) / b 
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a + d = d( x + c ) 
x + c = ( a + d ) / d 
x = ( ( a + d ) / d ) - c 
x = ( a + d - cd ) / d 
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ab / c = xd / c 
ab = xd 
x = ab / d