Bài giải:

$\frac{7x}{8}-5(x-9)=\frac{20x+1,5}{6}$

$\Leftrightarrow \frac{3.7x-5.24(x-9)}{24}=\frac{4(20x+1,5)}{24}$

$\Leftrightarrow $3.7x – 5.24 (x – 9) = 4(20x + 1,5)

$\Leftrightarrow $ 21x – 120x + 1080 = 80x + 6

$\Leftrightarrow $-99x + 1080 = 80x + 6

$\Leftrightarrow $-99x – 80x = 6 – 1080

$\Leftrightarrow $-179x = -1074

$\Leftrightarrow $x = -1074 : (-179)

$\Leftrightarrow $x = 6

Vậy x = 6