To solve for \( x \) in the equation \( -6x = -78 \), we can start by dividing both sides of the equation by -6:
\[ x = \frac{-78}{-6} \]
Now, simplify the right side:
\[ x = \frac{78}{6} \]
Calculating the division:
\[ x = 13 \]
Thus, the solution is:
\[ x = 13 \]