Question

equaçao do 2 grau 
x²+9=12x 

Answer 1

x² + 9 = 12x

x² + 9 - 12x = 0

x² - 12x  + 9 = 0

Resolvendo por Bháskara:

Δ = b²−4ac
Δ = (−12)²−4⋅1⋅9
Δ = 144−36
Δ = 108


x = -b ± √Δ / 2.a
x = -(-12) ± √108 / 2.1
x = 12 ± 6√3 / 2
x = 12 - 6√3 /2
x' = 6 - 3√3

x'' = 12 + 6√3 / 2
x'' = 6 + 3√3


S = {6 -  3√3 ,  6 + 3√3}