3x2+5x−13 x^{2}+5 x-13x2+5x−1
3x2−5x−13 x^{2}-5 x-13x2−5x−1
5x2+x−3=05 x^{2}+x-3=05x2+x−3=0
5x2−x−3=05 x^{2}-x-3=05x2−x−3=0