Question

0.6x^2+0.8x-7.8=0
Как решать?

Answer 1

0.6x²+0.8x-7.8=0
10(0.6x²+0.8x-7.8)=10*0
6x²+8x-78=0
D=8²-4*(-78)*6=64+1872=1936=44²
$x_{1}= frac{-8- sqrt{1936} }{2*6} = frac{-8-44}{12} = frac{-52}{12} =-4 frac{4}{12} =-4 frac{1}{3} \ x_{2}= frac{-8+ sqrt{1936} }{2*6} = frac{-8+44}{12} = frac{36}{12} =3$