in this case it is to find the roots of the polynomial.
We have then:
x ^ 2-12x + 59 = 0
Applying resolver we have
x = (- b +/- root (b ^ 2 - 4ac)) / (2a)
Substituting values:
x = (- (- 12) +/- root ((- 12) ^ 2 - 4 (1) (59))) / (2 (1))
x = (- (- 12) +/- root ((144 - 236)) / (2 (1))
x = (12 +/- root (-92))) / (2)
x = (6 +/- i * root (23)))
Answer:
x = (6 +/- i * root (23)))
(option 3)