b) \(\frac{10x+1}{7}=\frac{7x-2}{4}\)
<=> \(\frac{4\left(10x+1\right)}{28}=\frac{7\left(7x-2\right)}{28}\)
<=> 40x + 4 = 49x - 14
<=> 40x - 49x = -14 - 4
<=> -9x = -18
<=> x = 2
Vậy S = {2}
c) \(\frac{x-5}{5}-2=\frac{1+19x}{6}\)
<=> \(\frac{6\left(x-5\right)-60}{30}=\frac{5\left(1+19x\right)}{30}\)
<=> 6x - 30 - 60 = 5 + 95x
<=> 6x - 95x = 5 + 90
<=> -89x = 95
<=> x = -95/89
Vậy S = {-95/89}