a) \(\dfrac{x+5}{4}-\dfrac{x}{2}+1=0\)

<=> \(\dfrac{x+5-2x+4}{4}=0\)

<=> -x + 9 = 0 <=> x = 9

b) \(3\left(x+2\right)=\dfrac{x-4}{3}\)

<=> 9x + 18 = x-4

<=> 8x = -22

<=> x = \(\dfrac{-11}{4}\)

\(a,\Leftrightarrow x^3-4x^2+4x=0\\ \Leftrightarrow x\left(x^2-4x+4\right)=0\\ \Leftrightarrow x\left(x-2\right)^2=0\Leftrightarrow\left[{}\begin{matrix}x=0\\x=2\end{matrix}\right.\\ b,\Leftrightarrow4\left(x-1\right)=3x+6\left(2x-3\right)\\ \Leftrightarrow4x-4=3x+12x-18\\ \Leftrightarrow11x=14\Leftrightarrow x=\dfrac{14}{11}\)

a/ \(x^3-4x^2=-4x\)

\(\Leftrightarrow x^3-4x^2+4x=0\)

\(\Leftrightarrow x\left(x^2-4x+4\right)=0\)

\(\Leftrightarrow x\left(x-2\right)^2=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x-2=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=2\end{matrix}\right.\)

b/ \(\dfrac{x-1}{3}=\dfrac{x}{4}+\dfrac{2x-3}{2}\)

\(\Leftrightarrow8\left(x-1\right)=6x+12\left(2x-3\right)\)

\(\Leftrightarrow8x-8=6x+24x-36\)

\(\Leftrightarrow8x-8=30x-36\)

\(\Leftrightarrow8x-30x=8-36\)

\(\Leftrightarrow-22x=-28\)

\(\Leftrightarrow x=\dfrac{14}{11}\)

gúp minh với ạ 

a=6

a)58+7x=100

⇔7x=42

⇔x=6

b)4(x-51)=2.2²+20

⇔4x-204=28

⇔4x=232

⇔x=58

c)2x-49=5.3²

⇔2x-49=45

⇔2x=94

⇔x=47

A=6.