[(7+0.004x)/0.9]/24.7-12.3=77.7

[ (7+0.004x)/0.9] / 24.7    -   12.3 = 77.7[ (7+0.004x)/0.9] / 24.7  = 77.7 +12.3[ (7+0.004x)/0.9] = 90 * 24.7(7+0.004x)/0.9 = 22237+0.004x  = 2223*0.97+0.004x=2000.70.004x=2000.7 -70.004x= 1993.7x= 1993.7/0.004x= 498425Проверим:[( 7 + 0.004 *498425 ) / 0.9 ]  / 24.7    - 12.3 =77.7[ (7 +1993.7) /0.9]  / 24.7    -12.3 = 77.7[2000.7/0.9 ] /24.7  -  12.3 = 77.72223/24.7   - 12.3 = 77.790-12.3=77.777.7=77.7