Question

помогите пожалуйста очень срочно буду благодарна ​

Answer 1

$\displaystyle\bf\\x^{2} -3x+k=0\\\\x_{1} =2\\\\2^{2}-3\cdot 2+k=0\\\\4-6+k=0\\\\\boxed{k=2}\\\\Teorema \ Vieta:\\\\x_{1} +x_{2} =3\\\\x_{2} =3-x_{1} =3-2=1\\\\\boxed{x_{2}=1}$

$\displaystyle\bf\\2)\\\\x^{2}-6x-5=0\\\\Teorema \ Vieta:\\\\x_{1}+ x_{2} =6\\\\x_{1} \cdot x_{2}=-5\\\\\\\frac{1}{x_{1} }+\frac{1}{x_{2} }=\frac{x_{1} +x_{2} }{x_{1}\cdot x_{2} } =\frac{6}{-5} =-1,2\\\\\\\boxed{\frac{1}{x_{1} }+\frac{1}{x_{2} }=-1,2}$