well if you are trying to solve for g I would say that this one is difficult to try to factor and would use the quadratic equation instead which is:
g = (-b + or - squrt (b^2 - 4 * a * c)) / (2 * a)
the a b c represent the coefficients in order so we plug in and get
g = (37 + or - sqrt (37^2 - 4 * 12 * 28)) / (2 * 12)
working this out we get
g = (37 + or - sqrt(1369 - 1344)) / 24
g = (37 +- sqrt (25)) / 24
g = (37+- 5) / 24
g = 42 / 24 and 32 / 24
g = 7/4 and 4/3
