Question

resolva as equações do 2 grau, sendo U =R (x-3)(x+4)+8=x

Answer 1

$(x-3)(x+4)+8=x \\ \\ x^2+4x-3x-12+8-x=0 \\ \\ x^{2} +4x-3x-x-12+8=0 \\ \\ x^{2} +\not4x-\not4x-4=0 \\ \\ x^{2} -4=0 \\ \\ x^{2} =4 \\ \\ x=\pm \sqrt{4} \\ \\ x=\pm2 \\ \\ S=\{-2,+2\}$