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)3x-2/5=(-1)/10 b)2×(1/3)^x=2/27

Toán Lớp 7: Tìm x biết
a)3x-2/5=(-1)/10
b)2×(1/3)^x=2/27

Comments ( 2 )

  1. a) 3x – $\frac{2}{5}$ = $\frac{-1}{10}$ 
    =) 3x = $\frac{-1}{10}$ + $\frac{2}{5}$ 
    =) 3x = $\frac{3}{10}$ 
    =) x = $\frac{1}{10}$ 
    b) 2 x $(\frac{1}{3})^x$ = $\frac{2}{27}$ 
    =) ($\frac{1}{3})^x$ = $\frac{2}{27}$ : 2
    =) ($\frac{1}{3})^x$ = $\frac{1}{27}$
    =) ($\frac{1}{3})^x$ = ($\frac{1^3}{3^3})^3$
    =) x = 3

  2. 3x-2/3=(-1)/10
    3x       =(-1)/10 +2/3
    3x        =3/10 
    x          =3/10 : 3
    x          =1/10
    2×(1/3)^x=2/27
    (1/3)^x     =2/27 : 2
    (1/3)^x     =1/27
    (1/3)^x     =(1/3)^3
    x               =3
    chúc bn học tốt :))

Leave a reply

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

About Audrey