Question

resolva a equação do 2 grau x^2+8x+15=0

Answer 1

$x^{2} -8x+15=0\\ a+1\\ b=-8\\ c=15\\ \\ \Delta=b^2-4.a.c\\ \Delta=(-8)^2-4.1.15\\ \Delta=64-60\\ \Delta=4\\ \\ x=\frac{-b\pm\sqrt{\Delta}}{2a}\\ \\ x=\frac{8\pm\sqrt4}{2.1}=\frac{8\pm2}{2}\\ \\ x_1=\frac{8-2}{2}=\frac{6}{2}=3\\ \\ x_2=\frac{8+2}{2}=\frac{10}{2}=5\\ \\ S=\{3,5\}$