Question:
Solve -5*d - 52 = 8*d for d..

Answer:
-4

Question:
Solve -2*r + 99 - 117 = 0 for r..

Answer:
-9

Question:
Solve -970*n = -482*n - 541*n + 901 for n..

Answer:
17

Question:
Solve 0 = 7*l + 668 - 675 for l..

Answer:
1