Question:
Solve -9*p = -26*p - 13*p - 390 for p..

Answer:
-13

Question:
Solve 0*p = -5*p - 25 for p..

Answer:
-5

Question:
Solve 74*s = -206 - 16 for s..

Answer:
-3

Question:
Solve -19 + 17 - 192 = -97*v for v..

Answer:
2