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# Which of the following is a factor of x² – 5x – 6 ? A) (x + 2) B) (x – 6) C) (x – 3) D) (x – 2) E) (x – 1)

Gracie216

$x^2-5x- 6 =0\\ \\a=1, \ \ b=-5, \ \ c=-6, \ \ \\ \\\Delta = b^{2}-4ac =(- 5)^{2}-4*1*(-6)=25+24=49 \\ \\x_{1}=\frac{-b-\sqrt{\Delta }}{2a} =\frac{ 5- \sqrt{49}}{2}=\frac{5-7}{2}=- \frac{-2}{2}=-1\\ \\x_{2}=\frac{-b+\sqrt{\Delta }}{2a} =\frac{ 5+ \sqrt{49}}{2}=\frac{ 5+7}{2}=- \frac{ 12}{2}=6\\ \\x^2-5x-6 =(x-6)(x+1)\\ \\Answer : B) \ (x - 6)$