The expression that is equivalent to the given expression is (-5/8g - 1/2g - 19).
The expression on the left-hand side of the equation can be simplified as follows:
(3/4g-6-7/8g)-(1/2g 13)
= (3/4g-7/8g-6)-(1/2g+13)
= (-5/8g-6)-(1/2g+13) // Combine like terms.
= -5/8g-6 - 1/2g - 13 // Distribute the negative sign.
= -5/8g - 1/2g - 19 // Combine like terms.
Therefore, the expression that is equivalent to the given expression is (-5/8g - 1/2g - 19).