Question

$frac{x^2+x}{4}- frac{3-7x}{20} =0,3$

Answer 1

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

Answer 2

так