a) X + 2143 = 4465

     X = 4465 - 2143

     X = 2322

b) X - 2143 = 4465

     X = 4465 + 2143

     X = 6608

c) X : 2 = 2403

     X = 2403 x 2

     X = 4806

d) X x 3 = 6963

     X = 6963 : 3

     X = 2321

Bài 1: 

a) Ta có: \(\dfrac{17}{6}-x\left(x-\dfrac{7}{6}\right)=\dfrac{7}{4}\)

\(\Leftrightarrow\dfrac{17}{6}-x^2+\dfrac{7}{6}x-\dfrac{7}{4}=0\)

\(\Leftrightarrow-x^2+\dfrac{7}{6}x+\dfrac{13}{12}=0\)

\(\Leftrightarrow-12x^2+14x+13=0\)

\(\Delta=14^2-4\cdot\left(-12\right)\cdot13=196+624=820\)

Vì Δ>0 nên phương trình có hai nghiệm phân biệt là:

\(\left\{{}\begin{matrix}x_1=\dfrac{14-2\sqrt{205}}{-24}=\dfrac{-7+\sqrt{205}}{12}\\x_2=\dfrac{14+2\sqrt{2015}}{-24}=\dfrac{-7-\sqrt{205}}{12}\end{matrix}\right.\)

b) Ta có: \(\dfrac{3}{35}-\left(\dfrac{3}{5}-x\right)=\dfrac{2}{7}\)

\(\Leftrightarrow\dfrac{3}{5}-x=\dfrac{3}{35}-\dfrac{10}{35}=\dfrac{-7}{35}=\dfrac{-1}{5}\)

hay \(x=\dfrac{3}{5}-\dfrac{-1}{5}=\dfrac{3}{5}+\dfrac{1}{5}=\dfrac{4}{5}\)

ai giúp mik vs

\(x^2+3x=0\)

\(\Leftrightarrow x\left(x+3\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x+3=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=-3\end{matrix}\right.\)

\(x^2+3x=0\)

\(x\left(x+3\right)=0\)

x = 0 hoặc x +3 = 0

=> x = 0 hoặc x = -3

Vậy ...

\(\left(x+1\right)\left(x+3\right)-\left(x-2\right)\left(x+5\right)=2\)

\(\Leftrightarrow x^2+4x+3-x^2-3x+10=2\)

\(\Leftrightarrow x=-11\)

a) 7/x-1=x+1/9
7/x-x-1=1/9
7/x-x=1/9+1
7/x-x=10/9
còn lại thì bạn tự tính nhé
câu b làm tương tự

tick cho mik nha

a: Sửa đề: \(\left(x+2\right)^2+\left(x-1\right)^2-2\left(x-3\right)\left(x+3\right)=0\)

=>\(x^2+4x+4+x^2-2x+1-2\left(x^2-9\right)=0\)

=>\(2x^2+2x+5-2x^2+18=0\)

=>2x+23=0

=>2x=-23

=>\(x=-\frac{23}{2}\)

b: Sửa đề: \(2021x\left(x-2020\right)-x+2020=0\)

=>(x-2020)(2021x-1)=0

=>\(\left[\begin{array}{l}x-2020=0\\ 2021x-1=0\end{array}\right.\Rightarrow\left[\begin{array}{l}x=2020\\ 2021x=1\end{array}\right.\Rightarrow\left[\begin{array}{l}x=2020\\ x=\frac{1}{2021}\end{array}\right.\)

b: \(\Leftrightarrow3x-36-5x-175+x-15=0\)

\(\Leftrightarrow-x-226=0\)

hay x=-226

a) (x - 6)² = 9

\(\Rightarrow\left[{}\begin{matrix}x-6=3\\x-6=-3\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=9\\x=3\end{matrix}\right.\)

b) \(\left|x\right|=3\Leftrightarrow\left[{}\begin{matrix}x=3\\x=-3\end{matrix}\right.\)

ok

(x-1)/3 = -27

=> x-1 = (-27) . 3 = - 81

=> x = (-81)+1 = -80