Question

x^2 + 2x - 8 = 0
com fórmula de bhaskara

Answer 1

$x^2 + 2x - 8 = 0\\ \\a=1;b=2;c=-8\\\\\\ \Delta=b^2-4ac\to \Delta=2^2-4*1*(-8)\to \Delta=4+32\to \Delta=36\\\\\\ x= \frac{-b+- \sqrt{\Delta} }{2a} \to x= \frac{-2+- \sqrt{36} }{2*1} \to x= \frac{-2+- 6 }{2} \to \\\\\\ x'= \frac{-2+ 6 }{2} \to x'= \frac{4 }{2} \to x'=2\\ \\\\x''= \frac{-2- 6 }{2} \to x''= \frac{-8 }{2} \to x''=-4\\\\\\\\ S=(-4;2)$