The answer could be a or c but idk which one is the right one

2x2 -2x - 9 = 0
 For this case, what we should do is use the resolver.
 We have then:
 x = (- b +/- root (b ^ -4ac)) / 2a
 a = 2
 b = -2
 c = -9
 Substituting the values:
 x = (- (- 2) +/- root ((- 2) ^ - 4 (2) (- 9))) / 2 (2)
 Rewriting:
 x = (2 +/- root (4 + 72)) / 4
 x = (2 +/- root (76)) / 4
 x = (2 +/- root (19 * 4)) / 4
 x = (2 +/- 2raiz (19)) / 4
 x = (1 +/- root (19)) / 2
  
 option C
 x = (1 +/- root (19)) / 2