a, (x-3^2)=1 b,-4(5+35x^2)=-36

Question

a, (x-3^2)=1
b,-4(5+35x^2)=-36

in progress 0
Dâu 4 years 2020-10-17T09:02:56+00:00 2 Answers 88 views 0

Answers ( )

  1. Ben
    0
    2020-10-17T09:04:10+00:00
    Reply

    a/ x – 3² = 1

     x – 9 = 1

    x = 1 + 9 = 10

    b/ -4( 5 + 35x² ) = -36

        5 + 35x² = -36 : (-4) = 9

              35x² = 9 – 5 = 4

              x² = $\frac{4}{35}$ 

             

  2. Verity
    0
    2020-10-17T09:04:53+00:00
    Reply

    a, $(x-3^2)=1$
    $x=1+3^2$
    $x=1+9$
    $x=10$

    Vậy $x=10$

    b, Sửa đề: $-4(5+35x)^2=-36$
    $(5+35x)^2=-36:-4$
    $(5+35x)^2=9$
    $TH1: 5+35x=3$
    $35x=3-5$
    $35x=-2$
    $x=-2:35$
    $x=\dfrac{-2}{35}$
    $TH2: 5+35x=-3$
    $35x=-3-5$
    $35x=-8$
    $x=-8:35$
    $x=\dfrac{-8}{35}$
    Vậy `x∈{\frac{-2}{35}, \frac{-8}{35}}`

     

Leave an answer

Browse

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