Wilma and Greg were trying to solve the quadratic equation x^2 + bx + c = 0.Wilma wrote down the wrong value of b (but her value of c was correct), and found the roots to be 1 and 6. Greg wrote down the wrong value of c (but his value of b was correct), and found the roots to be -1 and -4. What are the actual roots of x^2 + bx + c = 0?