Question: What is the solution?

Solve g + 9*g = -3*g - 143 for g.

Answer: -11

Question: What is the solution?

Solve 630*a = -610*a + 843*a + 7940 for a.

Answer: 20

Question: What is the solution?

Solve 43*g + 16 - 220 = 1559 for g.

Answer: 41

Question: What is the solution?

Solve -2*r + 9 = 2*r - 3*r for r.

Answer:
9