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