Find the missing length indicated. Pls show ur work. Thank you.

#9
[tex]\\ \sf\longmapsto \dfrac{6}{12}=\dfrac{2x-7-14}{14}[/tex]
[tex]\\ \sf\longmapsto \dfrac{6}{12}=\dfrac{2x-21}{14}[/tex]
[tex]\\ \sf\longmapsto 12(2x-21)=72[/tex]
[tex]\\ \sf\longmapsto 2x-21=6[/tex]
[tex]\\ \sf\longmapsto 2x=27[/tex]
Now
[tex]\\ \sf\longmapsto 2x-7=27-7=20[/tex]
#10
[tex]\\ \sf\longmapsto \dfrac{24}{9}=\dfrac{40}{-x+30}[/tex]
[tex]\\ \sf\longmapsto 24(-x+30)=320[/tex]
[tex]\\ \sf\longmapsto -24x+720=320[/tex]
[tex]\\ \sf\longmapsto -24x=320-720=-400[/tex]
[tex]\\ \sf\longmapsto x=\dfrac{-400}{-24}[/tex]
[tex]\\ \sf\longmapsto x=16.6[/tex]