We are told to check for the correct equation that satisfies when the value of x = -12.
Let us resolve that by picking one of the options and testing it to confirm if it satisfies the value of x = -12.
Starting with OPTION B
[tex]15-\frac{1}{2}x=21[/tex]Solve for x
Subtract 12 from both sides
[tex]\begin{gathered} 15-15-\frac{1}{2}x=21-15 \\ -\frac{1}{2}x=6 \end{gathered}[/tex]Multiply both sides by 2
[tex]\begin{gathered} 2\times-\frac{1}{2}x=2\times6 \\ -1x=12 \end{gathered}[/tex]Divide both sides by -1
[tex]\begin{gathered} \frac{-1x}{-1}=\frac{12}{-1} \\ x=-12 \end{gathered}[/tex]From the solution, we can conclude that the above equation is true when the value of x = -12.
The correct option is Option B.