Question:
Solve -18*h = -19*h + 5 for h..

Answer:
5

Question:
Solve 0 = -3*v + v - 8 for v..

Answer:
-4

Question:
Solve 0 = -2*a - 11*a - 13 for a..

Answer:
-1

Question:
Solve -5*a + 15*a = -10 for a..

Answer:
-1