Question:
Solve 744 = -28*d + 44*d + 77*d for d..

Answer:
8

Question:
Solve s + 14 = 15 for s..

Answer:
1

Question:
Solve -218*r + 440 = -71*r - 103*r for r..

Answer:
10

Question:
Solve 5*r - 12 = -92 for r..

Answer:
-16