Решите уравнения: а)x^2+6x+5=0 б)2x^2-5x+3=0 в)2x^2-7x-4=0

Решите задачу:

$x^2+6x+5=0\\ D=36-20=16; \sqrt{D} =4\\ x_{1/2}= \frac{-6\pm4}{2}\\\\ x_1= -\frac{10}{2}=-5\\\\ x_2=- \frac{2}{2}=-1\\\\\\ 2x^2-5x+3=0\\ D=25-24=1; \sqrt{D} =1\\ x_{1/2}= \frac{5\pm1}{4}\\\\ x_1= \frac{4}{4} =1\\\\ x_2= \frac{6}{4} = \frac{3}{2}\\\\\\ 2x^2-7x-4=0\\ D=49+32=81; \sqrt{D}=9\\ x_{1/2}= \frac{7\pm9}{4}\\\\ x_1=- \frac{2}{4}=- \frac{1}{2}\\\\ x_2= \frac{16}{4}=4$