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: Bài 1 11, (x-5)-(2x+7)=-8 12, (x+1)+(x+2)…+(x+50)=1475 13, x+(-36)=33-|-103| 14, [(8x-12):4].3mũ6=3mũ9 15, 220+[2mũ4+(x+5)]=8mũ2.5 1

Toán Lớp 7: Bài 1
11, (x-5)-(2x+7)=-8
12, (x+1)+(x+2)…+(x+50)=1475
13, x+(-36)=33-|-103|
14, [(8x-12):4].3mũ6=3mũ9
15, 220+[2mũ4+(x+5)]=8mũ2.5
16, 213-(x-6)=1236:12
Giải Giúp Em Với !!!!

Comments ( 2 )

  1. $\\$
    11,
    (x-5) – (2x+7) = -8
    -> x-5 – 2x-7=-8
    -> (x-2x) + (-5-7) =-8
    -> -x – 12=-8
    -> -x=-8+12
    ->-x=4
    ->x=-4
    Vậy x=-4
    $\\$
    12,
    (x+1) + (x+2)+…+ (x+50)=1475
    ->x+1+x+2+…+x+50=1475
    ->  (x+x+…+x) + (1+2+…+50)=1475
    Số các số hạng của tổng trên là  :
    (50-1) : 1+1=50 số hạng 
    ->50x  + ( (50+1) . 50)/2=1475
    ->50x + 1275=1475
    -> 50x = 1475 – 1275
    -> 50x=200
    ->x=200:50
    ->x=4
    Vậy x=4
    $\\$
    13,
    x-36 = 33 – |-103|
    ->x-36=33-103
    ->x-36=-70
    ->x=-70+36
    ->x=-34
    Vậy x=-34
    $\\$
    14,
    [(8x-12):4] . 3^6 = 3^9
    -> (8x-12) :4=3^9 : 3^6
    -> (8x-12):4=3^3
    -> (8x-12):4=27
    -> 8x-12=27.4
    -> 8x-12=108
    -> 8x=108 + 12
    ->8x=120
    ->x=120 : 8
    ->x=15
    Vậy x=15
    $\\$
    15,
    220 + [2^4 + (x+5)] = 8^2 . 5
    -> 220 + [16 + (x+5)]=64 . 5
    -> 220 + [16 + (x+5)]=320
    -> 16 + (x+5) = 320 – 220
    -> 16 + (x+5)=100
    ->x+5=100-16
    ->x+5=84
    ->x=84-5
    ->x=79
    Vậy x=79
    $\\$
    16,
    213 – (x-6) = 1236 : 12
    -> 213 – (x-6)=103
    -> x-6=213-103
    ->x-6=110
    ->x=110+6
    ->x=116
    Vậy x=116

  2. Giải đáp + Lời giải và giải thích chi tiết:
    Bài 1 :
    11. (x-5)-(2x+7)=-8
    =>x-5-2x-7=-8
    =>-x=-8+7+5
    =>-x=4
    =>x=-4
    Vậy x = -4
    12. (x+1)+(x+2)+…+(x+50)=1475
    =>x+1+x+2+…+x+50=1475
    =>(x+x+…+x)+(1+2+…+50)=1475
    =>50x+[(1+50)*50]/2=1475
    =>50x+(51*50)/2=1475
    =>50x+1275=1475
    =>50x=200
    =>x=4
    Vậy x = 4
    13.
    x+(-36)=33-|-103|
    =>x-36=33-103
    =>x-36=-70
    =>x=-70+36
    =>x=-34
    Vậy x = -34
    14.
    [(8x-12):4]*3^6=3^9
    =>(8x-12):4=3^9:3^6
    =>(8x-12):4=3^3
    =>8x-12=3^3*4
    =>8x-12=27*4
    =>8x-12=108
    =>8x=108+12
    =>8x=120
    =>x=15
    Vậy x = 15
    15.
    220+[2^4+(x+5)]=8^2*5
    =>220+(16+x+5)=64*5
    =>220+16+x+5=320
    =>241+x=320
    =>x=79
    Vậy x = 79
    16.
    213-(x-6)=1236:12
    =>213-(x-6)=103
    =>x-6=213-103
    =>x-6=110
    =>x=116
    Vậy x = 116.
     

Leave a reply

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

About Mỹ anh