[latex] \frac{x^2+x}{4}- \frac{3-7x}{20} =0,3 [/latex]

[latex] \frac{5( x^{2} +x)-3+7x-0,3*20}{20}=0 \\ \frac{5 x^{2} +5x-3+7x-6}{20}=0 \\ \frac{5 x^{2} +12x-9}{20}=0 [/latex] 5x²+12x-9=0 D=(12)²-4*5*(-9)=324 x1=[latex] \frac{-12-18 }{2*5} [/latex]=-3 x2=[latex] \frac{-12+ 18}{2*5} [/latex]=0.6