Task: Question Answering
Input (English): Suppose 0 = f + 1, 17*f = 5*w + 12*f - 15. Suppose -3*s + 2 = -13. Suppose s*c + 3*j = 36, 3*c + 0*j - 18 = -3*j. Solve 20 = a - 5*z, -2*a + c = -w*z - 7 for a.
Output (English): 5