Question: What is the solution?

Solve -3205 = -321*d - 1255 + 3186 for d.

Answer: 16

Question: What is the solution?

Solve 8*r + 119 = 239 for r.

Answer: 15

Question: What is the solution?

Solve -191*t = 253 - 4073 for t.

Answer: 20

Question: What is the solution?

Solve 0 = -13*d - 1783 + 1640 for d.

Answer:
-11