[tex] \dfrac{x+8}{5x-2} = \dfrac{3}{8} [/tex]
Cross-multiply:
[tex]8(x + 8) = 3(5x - 2)[/tex]
Distribute 8 and 3:
[tex]8x + 64= 15x - 6[/tex]
Isolate x to the left:
[tex]15x - 8x = 64 + 6[/tex]
Combine like terms:
[tex]7x = 70[/tex]
Divide by 7:
[tex]x = 10[/tex]