Question

$x^{2} + 4x - 16=0$

Qual é o conjunto solução?

Answer 1

$x^{2} +4x-16=0\\\\\\a=1;b=4;c=-16\\\\ \Delta = b^{2} -4.a.c\to \to= 4^{2} -4.1.(-16)\to \Delta=16+64\to \Delta=80\\\\ x= \frac{-b+- \sqrt{\Delta} }{2.a} \to x= \frac{-4+- \sqrt{80} }{2.1} \to x= \frac{-4+- 8,9 }{2} \to \\\\x'=\frac{-4+ 8,9 }{2} \to x'=-\frac{4,9 }{2} \\\\ x''=\frac{-4- 8,9 }{2} \to x''=-\frac{12,9 }{2}\\\\\\S=(-\frac{4,9 }{2} ;-\frac{12,9 }{2})$