ANSWER:
B: 6(5/6x+2/3)=-9(6)
C: 5x+4=-54
F: 5x=-58
STEP-BY-STEP EXPLANATION:
We have the following equation
[tex]\begin{gathered} \frac{5}{6}x+\frac{2}{3}=-9 \\ 6\cdot(\frac{5}{6}x+\frac{2}{3})=-9\cdot6 \\ 5x+4=-54 \\ 5x=-58 \end{gathered}[/tex]Now, we analyze each option:
A.
[tex]\begin{gathered} 6\cdot(\frac{5}{6}x+\frac{2}{3})=-9 \\ \mleft\lbrace5x+4=-9\mright\rbrace\ne\mleft\lbrace(\frac{5}{6}x+\frac{2}{3})=-9\mright\rbrace \end{gathered}[/tex]B.
[tex]\begin{gathered} 6\cdot(\frac{5}{6}x+\frac{2}{3})=-9\cdot6 \\ \mleft\lbrace(\frac{5}{6}x+\frac{2}{3})=-9\}=\mright?(\frac{5}{6}x+\frac{2}{3})=-9 \end{gathered}[/tex]C.
[tex]\mleft\lbrace5x+4=-54\}\mright?=\mleft\lbrace\frac{5}{6}x+\frac{2}{3}=-9\mright\rbrace[/tex]D.
[tex]\lbrace5x+4=-9\}\ne\lbrace\frac{5}{6}x+\frac{2}{3}=-9\rbrace[/tex]E.
[tex]\mleft\lbrace5x=-13\}\mright?\ne\lbrace\frac{5}{6}x+\frac{2}{3}=-9\rbrace[/tex]F.
[tex]\mleft\lbrace5x=-58\mright\rbrace=\lbrace\frac{5}{6}x+\frac{2}{3}=-9\rbrace[/tex]Therefore the correct options are B, C and F