[tex]\it -5x^2-9x+2=0|_{\cdot(-1)} \Rightarrow 5x^2+9x-2=0,\ a=5,\ b=9,\ c=-2\\ \\ \Delta=b^2-4ac=9^2-4\cdot5\cdot(-2)=81+40=121\\ \\ \\ x_{1,2}=\dfrac{-b\pm\sqrt{\Delta}}{2a}=\dfrac{-9\pm\sqrt{121}}{2\cdot5}=\dfrac{-9\pm11}{10} \Rightarrow \begin{cases}\it x_1=\dfrac{-9-11}{10}=\dfrac{-20}{10}=-2\\ \\ \it x_2=\dfrac{-9+11}{10}=\dfrac{}{}\dfrac{\ 2^{(2}}{10}=\dfrac{1}{5}\end{cases}[/tex]
