Q: Solve 19*d = 7*d - 120 for d.

A: -10

Q: Solve 678 = -80*z + 6198 for z.

A: 69

Q: Solve 7995*u = 8589*u + 16038 for u.

A: -27

Q: Solve -402*v + 403*v = 5 for v.

A:
5