a) \(55-4x-4\left(-x+3\right)=6-2\left(-8-3x\right)\)
\(55-4x+4x-12=6+16+6x\)
\(43-6-16=6x\)
\(6x=21\)
\(x=3,5\)
b) \(-5\left(-2x-6\right)-9\left(4-7x\right)=51-3x+6\left(x-9\right)\)
\(10x+30-36+63x=51-3x+6x-54\)
\(73x-6=-3+3x\)
\(73x-3x=-3+6\)
\(70x=3\)
\(x=\frac{3}{70}\)
c) \(93+\left|6-3x\right|-39=231\)
\(\left|6-3x\right|+54=231\)
\(\left|6-3x\right|=177\)
\(\Rightarrow\orbr{\begin{cases}6-3x=177\\6-3x=-177\end{cases}}\Rightarrow\orbr{\begin{cases}3x=6-177\\3x=6+177\end{cases}}\Rightarrow\orbr{\begin{cases}3x=-171\\3x=183\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=-57\\x=61\end{cases}}\)
a) \(55-4x-4\left(-x+3\right)=6-2\left(-8-3x\right)\)
\(\Leftrightarrow\)\(55-4x+4x-12=6+16+6x\)
\(\Leftrightarrow\)\(6x+22=43\)
\(\Leftrightarrow\)\(6x=43-22=21\)
\(\Leftrightarrow\)\(x=21:6=3.5\)
Vậy...
b)pt\(\Leftrightarrow10x+30-36+63x=51-3x+6x-54\)
tự tiếp
\(93+\left|6-3x\right|-39=231\)
=> \(\left|6-3x\right|+54=231\)
=> \(\left|6-3x\right|=177=>\orbr{\begin{cases}6-3x=177\\3x-6=177\end{cases}=>}\orbr{\begin{cases}x=-57\\x=61\end{cases}}\)
\(55-4x-4\left(-x+3\right)=6-2\left(-8-3x\right)\)
\(=>55-4x+4x-12=6+16+6x\)
\(=>55-12=22+6x\)
\(=>43=22+6x\)
\(=>6x=43-22=21\)
\(=>x=\frac{21}{6}=3,5\)
Bài làm:
a,55- 4x - 4(-x+3) = 6 - 2(-8 - 3x)
\(\Leftrightarrow\) 55 – 4x + 4x - 12 = 6 + 16 + 6x
\(\Leftrightarrow\) 43 - 6 - 16 = 6x
\(\Leftrightarrow\) 21 = 6x
\(\Leftrightarrow\) x = 21 : 6
\(\Leftrightarrow\) x = 3,5
Vậy x = 3,5
b,-5(-2x - 6)- 9(4 - 7x) = 51 - 3x + 6(x - 9)
\(\Leftrightarrow\) 10x + 30 – 36 + 63x = 51 – 3x + 6x – 54
\(\Leftrightarrow\) 73 x – 6 = -3 + 3x
\(\Leftrightarrow\) 73x – 3x = -3 + 6
\(\Leftrightarrow\) 70x = 3
\(\Leftrightarrow\) x = \(\frac{3}{70}\)Vậy x = \(\frac{3}{70}\)
c,93 + |6-3x| - 39 = 231
|6 – 3x| + 54 = 231
|6 – 3x| = 177
TH1: 6 – 3x = 177 TH2: 6 – 3x = -177
=> 3x = 6 – 177 => 3x = 6 – ( -177)
=> 3x = - 171 => 3x = 183
=> x = (-171) : 3 => x = 183 : 3
=> x = -57 => x = 61
Vậy x = -57; x = 61
#Mạt Mạt#