решите уравнение 5*(0.2-х)=25       -9/14*z+2=2 4/7

5 * ( 0.2 - X ) = 25 1 - 5X = 25 5X = 26 X = 5.2 ==============- 9 / 14Z + 2 = 2 4/7 - 9 / 14Z = 2 4/7 - 2 - 9 / 14Z = 4/7 14Z = ( - 9 ) * 4/7 14Z = ( - 36/7 ) Z = ( - 36/7 ) : 14 Z = ( - 36/98 ) Z = ( - 18/49 )