( 1/3 ) * ( X + 1 ) - ( 2/3 ) * ( X - 1 ) = ( 2/3 ) * ( X - 3 )
общий знаменатель 3
X + 1 - 2 * ( X - 1 ) = 2 * ( X - 3 )
X + 1 - 2X + 2 = 2X - 6
- X + 3 = 2X - 6
2X + X = 3 + 6
3X = 9
X = 9 : 3
X = 3
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( 1/2 ) * ( 3X + 7 ) - ( 3/4 ) * ( 2X - 2 ) = ( 3/4 ) * ( X + 1 )
общий знаменатель 4
2 * ( 3X + 7 ) - 3 * ( 2X - 2 ) = 3 * ( X + 1 )
6X + 14 - 6X + 6 = 3X + 3
20 = 3X + 3
3X = 20 - 3
3X = 17
X = 17 : 3
X = 17/3 = 5 ( 2/3 )