What adds up to -54 and multiplies to -16

X + y = -54
xy = -16
















       
       

     x + y = -54
  2.8 + y = -54
- 2.8          - 2.8
           y = -56.8
     (x, y) = (2.8, -56.8)

             or

        x + y = -54
  -56.8 + y = -54
+ 56.8        + 56.8
              y = 2.8
        (x, y) = (-56.8, 2.8)

The two numbers that add up to -54 and multiply to -16 are -56.8 and 2.8.