Question

X² - 21x + 108 pleas answer the queastion

Answer 1

a= 1 b= -21 c= 108

D = b^2- 4ac

   =( -21)^2 - 4*1*108

    = 441 - 432

    = 9    root of 9 =3

x = -b +/- 3/2a

  21 + 3/2    ;        21-3/2

  24/2          ;       18/2

   12              ;         9

Therefore x = 12 and x = 9