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 6: tìm x: 2x+3=15 4-(x+3)=17 5-3(5-x)= -10

Toán Lớp 6: tìm x:
2x+3=15
4-(x+3)=17
5-3(5-x)= -10

Comments ( 2 )

  1. 2x + 3 = 15
            2x = 15 – 3
            2x = 12
              x = 12 : 2
              x = 6
    \text{Vậy,} x = 6
    ———————–
    4 – (x + 3) = 17
                x + 3 = 4 – 17
                x + 3 = $-13$
                         x = $-13 – 3$
                         x = $-16$
    \text{Vậy,} $x = -16$
    ————————
    $5 – 3(5 – x) = -10$
            $3(5 – x) = 5 – (-10)$
           3(5 – x) = 15
                 5 – x = 15 : 3
                 5 – x = 5
                          x = 5 – 5
                          x = 0
    \text{Vậy,} x = 0

  2. a, 2x + 3 = 15
      2x = 12
      x = 12 : 2
      x = 6
    Vậy x = 6
    b, 4 – (x + 3) = 17
      x + 3 = 4 – 17
      x + 3 = 4 + (-17)
      x + 3 = -13
      x = -13 – 3
      x = -13 + (-3)
      x = -16
    Vậy x = -16
    c, 5 – 3(5 – x) = -10
      3(5 – x) = 5 – (-10)
      3(5 – x) = 5 + 10
      3(5 – x) = 15
      5 – x = 15 : 3
      5 – x = 5
      x = 5 – 5
      x = 0
    Vậy x = 0

Leave a reply

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

About Khánh Ly