Register Now

Login

Lost Password

Lost your password? Please enter your email address. You will receive a link and will create a new password via email.

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

Toán Lớp 7: Tìm x biết : a) 2/3 x – (1/3 x + 1) = 2x – 5/3 b) 3/4 x – (1/2 x – 2) = 2/3 – (x + 2)

Toán Lớp 7: Tìm x biết :
a) 2/3 x – (1/3 x + 1) = 2x – 5/3
b) 3/4 x – (1/2 x – 2) = 2/3 – (x + 2)

Comments ( 1 )

  1. Giải đáp:
    a) x = 2/5
    b) x = (-8)/3
    Lời giải và giải thích chi tiết:
    a) 2/3 . x – ( 1/3 . x + 1 ) = 2x – 5/3
    => 2/3 . x –  1/3 . x – 1 = 2x – 5/3
    => 1/3 . x – 2x = – 5/3 + 1
    => 1/3 . x – 6/3 . x = (-2)/3
    => (-5)/3 . x = (-2)/3
    => x =  (-2)/3 . (-3)/5
    => x = 2/5
    Vậy x = 2/5
    b) 3/4 . x – ( 1/2 . x – 2 ) = 2/3 – ( x + 2 )
    => 3/4 . x – 1/2 . x + 2 = 2/3 – x – 2
    => 1/4 . x + x = 2/3 – 2 – 2
    => 1/4 . x + 4/4 . x = 2/3 – 12/3 
    => 5/4 . x = (-10)/3
    => x =  (-10)/3 . 4/5
    => x = (-8)/3
    Vậy x = (-8)/3

Leave a reply

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