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

Toán Lớp 7: 1. Thực hiện phép tính A. (-2/3)^2 + |-7/8| – 11/12 B. |-3/5|- 4/3 x (-9/12) C. -2/3 + 3/4 x |-4/9| 2. Tìm x biết A. |-3/2x – 5/3| =0

Toán Lớp 7: 1. Thực hiện phép tính
A. (-2/3)^2 + |-7/8| – 11/12
B. |-3/5|- 4/3 x (-9/12)
C. -2/3 + 3/4 x |-4/9|
2. Tìm x biết
A. |-3/2x – 5/3| =0
B. |x-1/3|= 1/4

Comments ( 2 )

  1. Bài 1:
    a) (-$\frac{2}{3}$)² + |-$\frac{7}{8}$| – $\frac{11}{12}$
    = $\frac{4}{9}$ + $\frac{7}{8}$ – $\frac{11}{12}$
    = $\frac{32}{72}$ + $\frac{63}{72}$ – $\frac{66}{72}$
    = $\frac{29}{72}$
    b) |-$\frac{3}{5}$| – $\frac{4}{3}$.(-$\frac{9}{12}$)
    = $\frac{3}{5}$ – $\frac{4}{3}$.(-$\frac{3}{4}$)
    =  $\frac{3}{5}$ + 1
    = $\frac{8}{5}$
    c) -$\frac{2}{3}$ + $\frac{3}{4}$.|-$\frac{4}{9}$|
    = -$\frac{2}{3}$ + $\frac{3}{4}$.$\frac{4}{9}$
    = -$\frac{2}{3}$ + $\frac{1}{3}$
    = -$\frac{1}{3}$
    Bài 2:
    a) |-$\frac{3}{2}$x – $\frac{5}{3}$| = 0
        -$\frac{3}{2}$x – $\frac{5}{3}$ = 0
        -$\frac{3}{2}$x = $\frac{5}{3}$
        x = -$\frac{10}{9}$
    Vậy x = -$\frac{10}{9}$
    b) |x – $\frac{1}{3}$| = $\frac{1}{4}$ 
    TH1: x – $\frac{1}{3}$ = $\frac{1}{4}$
            x = $\frac{7}{12}$ 
    TH2: x – $\frac{1}{3}$ = -$\frac{1}{4}$
            x = $\frac{1}{12}$
    Vậy x ∈ { $\frac{7}{12}$; $\frac{1}{12}$}

  2. 1
    a)(-2,3)^2 +|-7,8| -11/12
    =5,29+7,8- 11/12
    =907/75
    b)|-3,5| -4/3 xx (-9/12)
    =3,5 +3,225
    =0,275
    c)-2/3 +3/4 xx |-4/9|
    =-2/3 +1/3
    =-1/3
    2)
    a) |3,2x-5,3|=0
    ->3,2x-5,3=0
    3,2x=5,3
    x=5,3:3,2=53/32
    b)|x-1/3|=1/4
    TH1: x-1/3 =1/4
    x=1/4+1/3
    x=7/12
    TH2: x-1/3 =-1/4
    x=-1/4 +1/3=1/12
     

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