(4 1/5-а)-(а+5/7)=если,а=1 6/35

( 4 1/5 - а ) - ( а + 5/7 ) = 4 1/5 - а - а - 5/7 = - 2а + 4 7/35 - 25/35 = - 2а + 3 42/35 - 25/35 = 2а + 3 17/35 а = 1 6/35 = 41/35 2•( 41/35 ) + 3 17/35 = 82/35 + 3 17/35 = 2 12/35 + 3 17/35 = 5 29/35