Question

$x ^{2} - 6x + 9 = 0$

qual a resolução?​

Answer 1

$x {}^{2} - 6x + 9 = 0$

$a = 1 \: , \: b = - 6 \: , \: c = 9$

$∆ = b²-4ac \\ ∆ = ( - 6) {}^{2} - 4 \times 1 \times 9 \\ ∆ = 36 - 36 \\ ∆ = 0$

$x = \frac{ - b± \sqrt{∆} }{2 \times 1} \\ x = \frac{6± \sqrt{0} }{2} \\ x = \frac{6±0}{2} \\ x = \frac{6}{2} \\ x = \pink{3}$