Question:
Solve 0 = -3*a - 91 + 97 for a..

Answer:
2

Question:
Solve 3402*t = 2630*t - 20844 for t..

Answer:
-27

Question:
Solve 0 = -165*t + 173*t - 8 for t..

Answer:
1

Question:
Solve 0 = -42*r - 264 + 54 for r..

Answer:
-5