5/7(0.21-1/4х)-1=4/9(0,36-4,5х)

5/7*(0,21-1,4х)-4/9*(0,36-4,5х) = 10,15-1х - 0,16+2х = 12х-1х = 1-0,15+0,16х = 1,015/7*(0,21-1,4*1,01)-4/9*(0,36-4,5*1,01)= 5/7*(-1,204)- 4/9*(-4,185) = -0,86+1,86 = 1Ответ: 1,01.