What you must do in this case is to find the roots of the polynomial. We have then: x ^ 2 + 20x + 100 = 36 Rewriting: x ^ 2 + 20x + 64 = 0 The values of the roots are: x1 = -4 x2 = -16 Remember that the values of the roots are what make the polinome zero Answer: x1 = -4 x2 = -16