Question:
Solve -9*y + 15*y = 0 for y..

Answer:
0

Question:
Solve 1686 - 100 = 78*s - 832 for s..

Answer:
31

Question:
Solve 0 = -46*v + 119 + 157 for v..

Answer:
6

Question:
Solve 0 = -75*a - 20*a - 760 for a..

Answer:
-8