Respuesta :

-3=7+z/2
Subtract 7 from both sides
-10=z/2
Multipy 2 on both sides so that the only thing remaining on the right side is the variable z.
Final Answer: -20= z
Are you suppose to solve the equation to find z if so.. the answer would be 
z = -20 
Solve for z by simplifying both sides of the equation, then isolating the variable.