Question

Como resolver essa equação do 2grau x2-18x+45=0

Answer 1

$x^2-18x+45=0$

Coeficientes: a = 1, b = -18 e c = 45

$\Delta=b^2-4ac\\\Delta=(-18)^2-4\cdot1\cdot45\\\Delta=324-180\\\Delta=144$

$x=\frac{-b\pm\sqrt{\Delta}}{2a}\\\\x=\frac{-(-18)\pm\sqrt{144}}{2\cdot1}\\\\x=\frac{18\pm12}{2}\\\\x_1=\frac{18+12}{2}=\frac{30}{2}=15\\\\x_2=\frac{18-12}{2}=\frac{6}{2}=3$

Espero ter ajudado.
Bons estudos! :)