Question

por favor me ajudem qual as raizes reais de - x elevado a 2 + 3x + 10 = 0 ?

Answer 1

$-x^{2} + 3x + 10 = 0\\\\\\ a=-1~;~b=3~;~c=10\\\\\\ \Delta=b^2-4ac\to \Delta=3^2-4.(-1).10\to \Delta=9+40\to \boxed{ \Delta=49}\\\\ x' \neq x''\\\\\\ x= \dfrac{-b\pm \sqrt{\Delta} }{2a}\to~~ x= \dfrac{-3\pm \sqrt{49} }{2.(-1)}\to~~ x= \dfrac{-3\pm 7 }{-2}\to~~ \\\\\\x'= \dfrac{-3+ 7 }{-2}\to~~ x'= \dfrac{4}{-2}\to~~ \boxed{x'=-2} \\\\\\ x''= \dfrac{-3- 7 }{-2}\to~~ x''= \dfrac{-10 }{-2}\to~~ \boxed{x''=5}\\\\\\\\ \large\boxed{\boxed{S=\{-2~;~5\}}}$