6-х-1/2=3-х/2+х-2/3
12/2-х-1/2=9/3-х/2+х-2/3
11/2-х=7/3-х/2+х
х-х/2+х=11/2-7/3
2х-х/2=33/6-14/6
2х-х/2=19/6
(4х-х)/=19/6
3х=19/6:2
3х=19/6*1/2
3х=19/12
х=19/12:3
х=19/12*1/3
х=19/6
х=3 1/6
( x + 3 ) / 7 = ( 2x - 1 ) / 5
5( x + 3 ) = 7( 2x - 1 )
5x + 15 = 14x - 7
14x - 5x = 15 + 7
9x = 22
x = 2 4/9
9y²-6xy+x²+4x-12y= (3y-x)²+4(x-3y)=(3y-x)²-4(3y-x)= (3y-x)(3y-x-4)
Y²+7y+10-y²-7y-12=-2 при любом х