Question

2 x - (x + 1) = x + 1


Me ajudem por favor e pra amanhã

Answer 1

Resposta:

S {-1 ; 0,5}

Explicação passo-a-passo:

$2 x - (x + 1) = x + 1\\\\2x^2+2x = x+1\\\\2x^2+2x -x-1=0\\\\2x^2+x-1=0$

$\Delta = b^2 - 4ac\\\Delta = 1^2 - 4\cdot 2\cdot(-1)\\\Delta = 1+8\\\Delta = 9\\\\x'=\frac{-1+\sqrt{9} }{4} \\\\x'=\frac{-1+3 }{4} \\\\x'=\frac{2}{4} =\frac{1}{2} \\\\x''=\frac{-1-\sqrt{9} }{4} \\\\x''=\frac{-1-3 }{4} \\\\x''=\frac{-4 }{4} =-1$