Question: What is the solution?

Solve -2446 = 10*z + 21*z - 2632 for z.

Answer: 6

Question: What is the solution?

Solve d = -19 + 16 for d.

Answer: -3

Question: What is the solution?

Solve 38*c = 15*c - 92 for c.

Answer: -4

Question: What is the solution?

Solve 402*c - 145 = 423*c + 128 for c.

Answer:
-13