The concentration of toxic chemical in a spring fed lake is given by the equation c(x)= 50x/x^2+3x+6, where c is given in grams per litre and x is the time in days. Determine when the concentration of the chemical is 6.16 g/L.

50/x^2+3x+6= 6.16

50/x^2+3x+6 (x^2+3x+6) (6.16) = 6.16(6.16) (x^2+3x+6)

50(6.16)= 1(x^2+3x+6)

308=x^2+3x+6

0=x^2+3x+6-308

0=x^2+3x-302

Then solve using quadratic formula???? Im not sure if this is right.