Ecuaciones de 2do grado

x² -64 = 0
x² +15x +54 = 0
x² +11x +30 = 0
x² +15x +50 = 0
3x² -57x +270 = 0
-x² +13x -36 = 0
-x² -14x -48 = 0
3x² +33x +54 = 0
x² -7x -30 = 0
2x² +4x -30 = 0
x² +10x +21 = 0