Solve for the unknown:

2z - (z-1) = 5z - 15

z=4

Step-by-step explanation:

You would distribute the negative sign outside of the parentheses and get:

2z-z+1=5z-15

Then combine like terms and get:

z+1=5z-15

Subtract 5z from both sides:

-4z+1=-15

Subtract 1 from both sides:

-4z=-16

Then divide both sides by - 4:

z=4