Tìm x biết (x – 2)(2x + 4) – 2x(x + 1) = 0

Question

Tìm x biết (x – 2)(2x + 4) – 2x(x + 1) = 0

in progress 0
Verity 6 years 2020-10-14T12:05:52+00:00 2 Answers 186 views 0

Answers ( )

  1. Giakhanh
    0
    2020-10-14T12:07:18+00:00
    Reply

    $(x-2)(2x+4)-2x(x+1)=0$

    $⇔2(x-2)(x+2)-2x^2-2x=0$

    $⇔2(x^2-4)-2x^2-2x=0$

    $⇔2x^2-8-2x^2-2x=0$

    $⇔-2x-8=0$

    $⇔-2(x+4)=0$

    $⇔x+4=0$

    $⇔x=-4$

    $\text{Vậy $x=-4$}$

  2. dangkhoa
    0
    2020-10-14T12:07:46+00:00
    Reply

    Đáp án:

     $x=-4$

    Giải thích các bước giải:

     $(x-2).(2x+4)-2x.(x+1)=0$

    $⇔2x^2-8-2x^2-2x=0$

    $⇔-2x-8=0$

    $⇔-2x=8$

    $⇔x=-4$

Leave an answer

Browse

Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )