Rozwiąż równanie kwadratowe 2x2+8x-10=0 2x2-7x=-30-2x(1-x)

[latex]a)\ \2x^2+8x-10=0 \ \Delta = b^{2}-4ac = 8^{2}-4*2*(-10)=64+80=144 \ \sqrt{Delta }=sqrt{144}=12\ \x_{1}=frac{-b-sqrt{Delta }}{2a} =frac{-8-12}{4}=frac{-20}{4}=-5[/latex] [latex]x_{2}=frac{-b+sqrt{Delta }}{2a} =frac{-8+12}{4}=frac{4}{4}= 1[/latex] [latex]b)\ \2x^2-7x=-30-2x(1-x)\ \2x^2-7x=-30-2x+2x^2\ \2x^2-7x+2x-2x^2=-30\ \-5x=-30/:(-5)\ \x=6[/latex]