1) Ta có: \(3\left(x-1\right)-5\left(x-2\right)=4\left(x+1\right)\)

\(\Leftrightarrow3x-5-5x+10-4x-4=0\)

\(\Leftrightarrow-6x+1=0\)

\(\Leftrightarrow-6x=-1\)

hay \(x=\dfrac{1}{6}\)

2) Ta có: \(-2\left(x-2\right)-4\left(x+1\right)=-3\left(x+3\right)\)

\(\Leftrightarrow-2x+4-4x-4+3x+9=0\)

\(\Leftrightarrow-3x=-9\)

hay x=3

3) Ta có: \(3x^2+2x=0\)

\(\Leftrightarrow x\left(3x+2\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=-\dfrac{2}{3}\end{matrix}\right.\)

4) Ta có: \(x^2-5x=0\)

\(\Leftrightarrow x\left(x-5\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=5\end{matrix}\right.\)

5) Ta có: \(\left(2x-3\right)^2=36\)

\(\Leftrightarrow\left[{}\begin{matrix}2x-3=6\\2x-3=-6\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}2x=9\\2x=-3\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{9}{2}\\x=-\dfrac{3}{2}\end{matrix}\right.\)

6) Ta có: \(\left(5x-1\right)^3=125\)

\(\Leftrightarrow5x-1=5\)

\(\Leftrightarrow5x=6\)

hay \(x=\dfrac{6}{5}\)

7) Ta có: \(3^{x+1}=27\)

\(\Leftrightarrow x+1=3\)

hay x=2

5^x+4=1257

5^x.5⁴=1257

5^x      =1257 : 5⁴   

5^x      =1257 : 625

5^x     =2.0112

chị chỉ biết đến đây thôi

chị lớp 7 nhé

a)   \(\left(743-569\right)-\left(431-1257+996\right)\)

\(=743-569-431+1257-996\)

\(=\left(743+1257\right)-\left(569+431\right)-996\)

\(=2000-1000-996\)

\(=4\)

a. (2x - 612) + (-303) = 111-x

2x - 612 - 303 = 111 - x

2x - (612+303) = 111 - x

2x - 915 = 111 - x

2x + x = 111 + 915

3x = 1026

x = 1026 : 3

x = 342

vậy_____

a)=234(1257-257)

=234.1000

=234000

b)=524(1327-327)

=524.1000

=524000

c)=325(1574-325-24)

=325.1225

=398125

d)=175(1274-273-1)

=175.1000

=175000

234x (1257-257)= 234 x 1000 = 234000

1327 x 524 - 524 x 327 = 524 x (1327 - 327 ) = 524 x 1000 = 524000

325x1574 - 325 x 325 -325 x24 =325 x(1574 - 325 - 24 )= 325 x 1225 =398125

175 x 1274 - 175 x273 -175 = 175 x (1274 - 273 -1) = 175 x 1000= 175000

                 kkk mk nha bạn !!!!!!!!

1/a)Ta có -5=-1*5=-5*1

​Sau đó bn lập bảng rồi dùng ước bội để tính nhé​

​ Tk mình nha bn!