Algebra

 

Find the discriminant of the quadratic 5x^2 - 2x + 8 - 2x^2 + 6x + 2 - 2x^2 + 4x - 1.    

 

First, collect and combine like terms   

and arrange them as ax² + bx + c           (5x² – 2x² – 2x²) + (–2x + 6x + 4x) + (+8 + 2 – 1)    

 

                                                                  x² + 8x + 9    

 

The discriminant is b² – 4ac                     D  =  8² – (4)(1)(9)    

 

                                                                 D  =  64 – 36    

 

                                                                 D  =  28    

_.