Q: What is the solution?
Solve 0 = 213*a - 61*a + 912 for a.

A: -6

Q: What is the solution?
Solve 219*u + 1596 - 393 = -355 - 3041 for u.

A: -21

Q: What is the solution?
Solve 56*z - 145*z = 1683 - 526 for z.

A:
-13