
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.


a)-5 ( 3x - 7 ) - ( -15x +3 ) - ( 12-x )= -4
=>-15x+35+15x-3-12+x=-4
=>(-15x+15x)+(35-3-12)+x=-4
=>0+20+x=-4
=>20+x=-4
=>x=-4-20
=>x=-24
b)-3 ( 4x -2 ) - ( -12x +8 ) - (-x)=0
=>-12x+6+12x-8+x=0
=>(-12x+12x)+(6-8)+x=0
=>0+(-2)+x=0
=>(-2)+x=0
=>x=0-(-2)
=>x=2

Bài 1:
a: \(\Leftrightarrow\dfrac{6}{7}\left(\dfrac{7}{12}x-\dfrac{14}{3}\right)=\dfrac{5}{9}-\dfrac{9}{8}=\dfrac{-41}{72}\)
\(\Leftrightarrow x\cdot\dfrac{7}{12}-\dfrac{14}{3}=-\dfrac{287}{432}\)
\(\Leftrightarrow x\cdot\dfrac{7}{12}=\dfrac{1729}{432}\)
hay \(x=\dfrac{247}{36}\)
b: \(\Leftrightarrow\dfrac{1}{5}:x=\dfrac{1}{5}+\dfrac{3}{14}-\dfrac{8}{7}=\dfrac{-51}{70}\)
hay \(x=-\dfrac{14}{51}\)
c: đề sai rồi bạn

a,
128-3x-12=23
3x=128-12-23
3x=93
x=93:3
= 31
b,
(12x+84+55):5=35
12x+84+55=35.5
12x+84+55=175
12x=175-55-84
12x=36
x=36:12
x=3

x(5-12)+8(7-16)+12x-15(17-56)=0
x.(-7)+8.(-9)+12x-15.(-39)=0
x.(-7)+12x-72+585=0
x(-7+12)+513=0
x.5=-513
x=-513/5

a: =>3(x+4)=115
=>x+4=115/3
hay x=103/3
b: =>\(8^3\cdot\left(12x-64\right)=4\cdot8^4\)
\(\Leftrightarrow12x-64=32\)
=>12x=96
hay x=8
c: \(\Leftrightarrow\left(4x+28\right)\cdot23+55=175\)
=>(4x+28)x23=120
=>4x+28=120/23
=>4x=-524/23
hay x=-131/23