Verified answer

По теореме Виета:

[tex]x_{1}+x_{2}=-\frac{4}{5}\\\\ x_{1}\cdot x_{2}=-\frac{9}{5}[/tex]

[tex]x_{1}\cdot x_{2}-4x_{1}-4x_{2}=x_{1}\cdot x_{2}-4(x_{1}+ x_{2})=-\frac{9}{5}-4\cdot (-\frac{4}{5})=\frac{7}{5}=1,4[/tex]

По теореме Виета:

[tex]x_{1}+x_{2}=\frac{5}{3}\\\\ x_{1}\cdot x_{2}=\frac{8}{3}[/tex]

[tex]x_{1}\cdot x_{2}-4x_{1}-4x_{2}=x_{1}\cdot x_{2}-4(x_{1}+ x_{2})=\frac{8}{3}-4\cdot (\frac{5}{3})=-\frac{12}{3}=-4[/tex]