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222-9+11+12:2*14+14 = ? ( )

Toán Lớp 8: a.x(x + 4)- 5 x – 20 = 0 b,x( x – 3 ) – 3 x mũ 2 + 9X = 0 c,( x – 7)(x + 5) -( x + 5 ) (5 x+1)=0 d.3 x( x – 2)-( x – 2 )( x + 15 )= 0 m

Home/ Toán Lớp 8: a.x(x + 4)- 5 x – 20 = 0 b,x( x – 3 ) – 3 x mũ 2 + 9X = 0 c,( x – 7)(x + 5) -( x + 5 ) (5 x+1)=0 d.3 x( x – 2)-( x – 2 )( x + 15 )= 0 m

Toán Lớp 8: a.x(x + 4)- 5 x – 20 = 0 b,x( x – 3 ) – 3 x mũ 2 + 9X = 0 c,( x – 7)(x + 5) -( x + 5 ) (5 x+1)=0 d.3 x( x – 2)-( x – 2 )( x + 15 )= 0 m

Tháng Bảy 22, 2022 Toán học 1 Comment 0 views

Toán Lớp 8: a.x(x + 4)- 5 x – 20 = 0 b,x( x – 3 ) – 3 x mũ 2 + 9X = 0 c,( x – 7)(x + 5) -( x + 5 ) (5 x+1)=0 d.3 x( x – 2)-( x – 2 )( x + 15 )= 0 mong các bạn giúp minh với mình đang cần gấp
mình vote 5 sao

Comments ( 1 )

  1. cobexinhdep
    cobexinhdep
    22 Tháng Bảy, 2022 at 9:22 chiều
    Reply
    Giải đáp:
    $a.$ \(\left[ \begin{array}{l}x=-4\\x=5\end{array} \right.\) 
    $b.$ \(\left[ \begin{array}{l}x=0\\x=3\end{array} \right.\) 
    $c.$ \(\left[ \begin{array}{l}x=-5\\x=-2\end{array} \right.\) 
    $d.$ \(\left[ \begin{array}{l}x=2\\x=\frac{15}{2}\end{array} \right.\) 
    Lời giải và giải thích chi tiết:
    $a. x( x + 4 ) – 5x – 20 = 0$
    ⇔ $x( x + 4 ) – 5( x + 4 ) = 0$
    ⇔ $( x + 4 )( x – 5 ) = 0$
    ⇔ \(\left[ \begin{array}{l}x=-4\\x=5\end{array} \right.\) 
    $b. x( x – 3 ) – 3x^{2} + 9x = 0$
    ⇔ $x( x – 3 ) – ( 3x^{2} – 9x ) = 0$
    ⇔ $x( x – 3 ) – 3x( x – 3 ) = 0$
    ⇔ $- 2x( x – 3 ) = 0$
    ⇔ \(\left[ \begin{array}{l}x=0\\x=3\end{array} \right.\) 
    $c. ( x – 7 )( x + 5 ) – ( x + 5 )( 5x + 1 ) = 0$
    ⇔ $( x + 5 )( x – 7 – 5x – 1 ) = 0$
    ⇔ $( x + 5 )( – 4x – 8 ) = 0$
    ⇔ $- 4( x + 5 )( x + 2 ) = 0$
    ⇔ $( x + 5 )( x + 2 ) = 0$
    ⇔ \(\left[ \begin{array}{l}x=-5\\x=-2\end{array} \right.\) 
    $d. 3x( x – 2 ) – ( x – 2 )( x + 15 ) = 0$
    ⇔ $( x – 2 )( 3x – x – 15 ) = 0$
    ⇔ $( x – 2 )( 2x – 15 ) = 0$
    ⇔ \(\left[ \begin{array}{l}x=2\\2x=15\end{array} \right.\) 
    ⇔ \(\left[ \begin{array}{l}x=2\\x=\frac{15}{2}\end{array} \right.\) 

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222-9+11+12:2*14+14 = ? ( )

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