a: \(\left(x+\dfrac{1}{4}\right)+\left(3x-4\right)+2\left(x-3\right)=1\)

=>\(x+\dfrac{1}{4}+3x-4+2x-6=1\)

=>\(6x-\dfrac{39}{4}=1\)

=>\(6x=1+\dfrac{39}{4}=\dfrac{43}{4}\)

=>\(x=\dfrac{43}{4}:6=\dfrac{43}{24}\)

b: \(2\left(x-3\right)=3\left(x+2\right)-x+1\)

=>\(2x-6=3x+6-x+1\)

=>2x-6=2x+7

=>-6=7(vô lý)

c: \(x\left(x+3\right)+x\left(x-2\right)=2x\left(x-1\right)\)

=>\(x^2+3x+x^2-2x=2x^2-2x\)

=>3x-2x=-2x

=>3x=0

=>x=0

d: \(\left(x-1\right)\cdot3x-2\left(x+2\right)-2x=x\left(x-1\right)\)

=>\(3x^2-3x-2x-4-2x=x^2-x\)

=>\(3x^2-7x-4-x^2+x=0\)

=>\(2x^2-6x-4=0\)

=>\(x^2-3x-2=0\)

=>\(x=\dfrac{3\pm\sqrt{17}}{2}\)

x + 2.x + 3.x + 4.x + ... + 100.x = 5050

x.(1 + 2 + 3 + 4 + ... + 100) = 5050

x.(1 + 100).100:2 = 5050

x.101.50 = 5050

x.5050 = 5050

x = 5050 : 5050

x = 1

Vậy x = 1

x x 8,6=387

       x= 387: 8,6

       x= 45

9,5 x x= 399

         x= 399: 9,5

         x= 42

tk nhé

x=6 nhé

1: =>0,5:(0,4-x)=2,5

=>0,4-x=0,5/2,5=0,5

=>x=0,4-0,5=-0,1

2: =>x*(3,6+6,4)=18,9

=>10x=18,9

=>x=1,89

3: =>(9,4+5,3):x=14

=>14,7:x=14

=>x=14,7/14=1,05

\(\frac{4}{\frac{2}{5}}:\left(-\frac{33}{10}\right)+x=-\frac{1}{\frac{5}{6}}\)

\(10:\left(-\frac{33}{10}\right)+x=-\frac{6}{5}\)

\(-\frac{100}{33}+x=-\frac{6}{5}\)

\(x=\frac{302}{165}\)