2х-7=5х-4; 2х-5х=-4+7; -3х=3; х=-1.
( 2X - 7 ) / 3 = ( 5X - 4 ) / 5 5 * ( 2X - 7 ) = 3 * ( 5X - 4 ) 10X - 35 = 15X - 12 15X - 10X = 12 - 35 5X = - 23 X = - 4,6