Question: What is the solution?

Solve -3*k = -57 + 45 for k.

Answer: 4

Question: What is the solution?

Solve 0 = -13341*r + 13350*r + 9 for r.

Answer: -1

Question: What is the solution?

Solve 119*i = 139*i + 160 for i.

Answer: -8

Question: What is the solution?

Solve -4592*k - 52158 - 60220 + 15946 = 0 for k.

Answer:
-21