Нужно решения этого примера

Решите задачу:

$y=- x^{2} +6x-5 \\ y=0\\- x^{2} +6x-5=0\\ x^{2} -6x+5=0\\D=36-20=16\\ \sqrt{D} =4\\ x_{1} = \frac{6+4}{2} =5\\ x_{2} = \frac{6-4}{2} =1$

$y=- x^{2} +6x-5 \\ y=2\\ \\ - x^{2} +6x-5=2\\- x^{2} +6x-5-2=0\\- x^{2} +6x-7=0\\ x^{2} -6x+7=0\\D=36-28=8 \\ \sqrt{D} =2 \sqrt{2} \\ x_{1} = \frac{6-2 \sqrt{2} }{2} = \frac{2(3- \sqrt{2}) }{2} =3- \sqrt{2} \\ x_{1} = \frac{6+2 \sqrt{2} }{2} = \frac{2(3+ \sqrt{2}) }{2} =3+ \sqrt{2}$

$y=- x^{2} +6x-5 \\ y=3\\- x^{2} +6x-5=3\\- x^{2} +6x-5-3=0\\- x^{2} +6x-8=0\\ x^{2} -6x+8=0\\D=36-32=4\\ \sqrt{D} =2\\ x_{1} = \frac{4+2}{2} =3\\ x_{2} = \frac{4-2}{2} =1$