Toán Lớp 6: -x-2=5/4 5/4+x=2/3 2/3+13.-2/5 |1/5.x+4|=1/3-1/5

Question

Toán Lớp 6:  -x-2=5/4 5/4+x=2/3 2/3+13.-2/5 |1/5.x+4|=1/3-1/5

quynhthanhnhu · Answer

-x - 2 = 5/4   -x = 5/4 + 2   -x = 13/4   =>x = -13/4   Vậy x = -13/4      5/4 + x = 2/3   x = 2/3 - 5/4   x = -7/12   Vậy x = -7/12      2/3 +  13 . (-2)/5   = 2/3 + (-26)/5   = 10/15 - 78/15   = -68/15      |1/5 . x + 4| = 1/3 - 1/5   |1/5 . x + 4| = 2/15   =>+) Trường hợp 1 :   1/5 . x + 4 = 2/15   1/5 . x = 2/15 - 4   1/5 . x = -58/15   x = -58/15 : 1/5   x=-59/3   +) Trường hợp 2 :   1/5 . x + 4 = -2/15   1/5 . x = -2/15 - 4   1/5 . x = -62/15   x = -62/15 : 1/5   x= -62/3   Vậy x  in { -59/3 ; -62/3}   #caty09

haiyemy · Answer

Giải đáp + Lời giải và giải thích chi tiết:    -x - 2 = 5/4    -x       = 5/4 + 2    -x       = 5/4 + 8/4    -x       = 13/4   => x   = -13/4    Vậy x = -13/4   5/4 + x = 2/3    x          = 2/3 - 5/4    x          = 8/12 - 15/12    x          = -7/12   Vậy x = -7/12   2/3 + 13 . (-2)/5    = 2/3 - 26/5    = 10/15 - 78/15    = -68/15   |1/5x + 4| = 1/3 - 1/5    |1/5x + 4| = 5/15 - 3/15   | 1/5x + 4| = 2/15   => 1/5x + 4 = 2/15 hoặc 1/5x + 4 = -2/15   Nếu 1/5x + 4 = 2/15          ;           Nếu 1/5x + 4 = -2/15    1/5x = 2/15 - 4                   ;              1/5x = -2/15 - 4    1/5x = -58/15                   ;                1/5x = -62/15    x       = -58/3                    ;             x = -62/3   Vậy x  in {-58/3 ; -62/3}