Question

найдите корень уравнения:1)(1,8+x)×21=71,4.2) 16 (4x-3,4)=6,08.3)(x-1,25)×4,5=27.4)(x+19.64)×0,18=144.5) 17 (1,6-5x)=2.38.6) 9,66÷(x+0,17)=23

Answer 1

 
  1)(1.8+х)*21=71.4
((9/5)+x)*21 = 71.4  9/5+x)*21 = 71.4     21*x = 33.6     x = 33.6 / (21)   x = 1.6    
2)16*(4*x-(17/5)) = 6.08   16*4*x+16*17/5) = 6.08     64*x = 60.48     x = 60.48 / (64)   x = 0.945   3)(x-1.25)*(4.5) = 27   (x-1.25)*(9/2) = 27   x-1.259/2 = 27     9*x/2 = 32.625     x = 32.625 / (9/2)      x = 7.25       4)(x+19.64)*0.18 = 144     x*0.18+19.64*0.18 = 144       x = 140.4648 / (0.18)   x = 780.36 5) 17 (1,6-5x) = 2.38   17*(8/5-5*x) = 2.38     -85*x = -24.82   Разделим обе части ур-ния на -85   x = -24.82 / (-85)   x = 0.292 6) 9,66÷(x+0,17)=23 9.66/(х+0.17)=23 9.66=(х+0.17)*23 9.66=23х+3.91,  23х=5.75 x = 0.25