Toán Lớp 8: 3x(x-2020)-x+2020=0 giải theo 2 cách giúp mình

Question

Toán Lớp 8:  3x(x-2020)-x+2020=0 giải theo 2 cách giúp mình

tuyetnhungthu · Answer

Giải đáp:       Lời giải và giải thích chi tiết:    c1: (x-2020)(3x-1)=0   &hArr;x-2020=0  &hArr;x=2020       3x-1=0  &hArr;x=1/3   Vay x&isin;{2020: 1/3}   c2 &hArr;3x&sup2;-6060x-x+2020=0   &hArr;3x(x-2020)-x+2020=0   (x-2020)(3x-1)=0   &hArr;x-2020=0  &hArr;x=2020       3x-1=0  &hArr;x=1/3   Vay x&isin;{2020: 1/3}

mocmien87 · Answer

C&aacute;ch thứ nhất :   3x(x-2020) - x+2020 =0   => 3x(x-2020) -(x-2020) =0   => (3x-1)(x-2020) =0   => (3x-1)(x-2020) =0   =>  ( left[  begin{array}{l}3x-1 =0   x-2020 =0 end{array}  right. )    =>  ( left[  begin{array}{l}x= dfrac{1}{3}  x=2020 end{array}  right. )    Vậy S  in {1/3 ; 2020}   $  $   C&aacute;ch thứ hai :   3x(x-2020) - x +2020 =0   => 3x^2 - 6060x - x +2020 =0     => 3x^2 - 6061x +2020 =0   =>(3x-1)(x-2020) =0   =>  ( left[  begin{array}{l}3x-1 =0   x-2020 =0 end{array}  right. )    =>  ( left[  begin{array}{l}x= dfrac{1}{3}  x=2020 end{array}  right. )    Vậy S  in {1/3 ; 2020}