\(3\left(x-2\right)+4\left(x-1\right)=25\) 

\(\Leftrightarrow3x-6+4x-4=25\) 

\(\Leftrightarrow7x=35\) 

\(\Leftrightarrow x=5\)

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

\(\Leftrightarrow\left(5x-3\right)\left(x-2\right)-\left(x-1\right)\left(x-2\right)=0\) 

\(\Leftrightarrow\left(x-2\right)\left(5x-3-x+1\right)=0\) 

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

\(\Leftrightarrow\left[{}\begin{matrix}x-2=0\\4x+2=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=2\\x=\dfrac{-1}{2}\end{matrix}\right.\)

\(\left(x-2\right)^2=4\left(x-1\right)^2\)

\(\Leftrightarrow\left(x-2\right)^2-4\left(x-1\right)^2=0\) 

\(\Leftrightarrow\left[\left(x-2\right)-2\left(x-1\right)\right]\left[\left(x-2\right)+2\left(x-1\right)\right]=0\) 

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

\(\Leftrightarrow\left(-x\right)\left(3x-4\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}-x=0\\3x-4=0\end{matrix}\right.\) 

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=\dfrac{4}{3}\end{matrix}\right.\)

1: =>x=8-35=-27

2: =>15-4+x=6

=>x+11=6

hay x=-5

3: =>-30+25-x=-1

=>x+5=1

hay x=-4

4: =>x-(-13)=-8

=>x+13=-8

hay x=-21

5: =>x-29-17+38=-9

=>x-8=-9

hay x=-1

a,x=4 hoặc -6

b,x=3

Cần lời giải ko bn

a) (x+1) ^2 = 25

    (x+1) ^2 = 5^2

    x  + 1   = 5            Hoặc x + 1 = -5

    x          = 5 - 1                x       = -5 - 1

    x          = 4                     x       = -6

b) 4^5.4^x-1 = 4^7

          4^x-1 = 4^7:4^5

          4^x-1 = 4^7-5

          4^x-1 = 4^2

             x- 1 = 2

              x    = 2+1

              x    = 3

 a, x+4/7=7/4-1/4

x + 4/7 = 6/4 

x = 6/4 - 4/7 

x = 26/28

b,   9/2+(x-3/4)=25/4

x - 3/4 = 25/4 - 9/2

x - 3/4 = 7/4

x = 7/4 + 3/4 

x = 10/4

a, x+4/7=7/4-1/4 

x+4/7= 3/2

x = 3/2-4/7= 13/14

b,9/2+(x-3/4)=25/4

x-3/4 = 25/4 - 9/2 = 7/4

x= 7/4 + 3/4 = 5/2

\(a,x+\frac{4}{7}=\frac{7}{4}-\frac{1}{4}\)

\(x+\frac{4}{7}=\frac{3}{2}\)

\(x=\frac{3}{2}-\frac{4}{7}\)

\(x=\frac{13}{14}\)

\(b,\frac{9}{2}+\left(x-\frac{3}{4}\right)=\frac{25}{4}\)

\(x-\frac{3}{4}=\frac{25}{4}-\frac{9}{2}\)

\(x-\frac{3}{4}=\frac{7}{4}\)

\(x=\frac{7}{4}+\frac{3}{4}\)

\(x=\frac{5}{2}\)

a) Ta có: 6 x 3 = 48 nên x 3 = 8 . Do đó x = 2.

b) Ta có: ( x - 1 ) 2 = 2 2  nên x -1 = 2. Do đó x = 3.

c) Ta có: ( x + 1 ) 2 = 5 2  nên x +1 = 5. Do đó x = 4.

a)  4^x = 64

     4^x =  4³

=> x = 3

c)   5^x+2 = 25

      5^x+2 = 5²

=> x + 2 = 2

=>        x = 0

mình thấy phần b hình như sai đề

Có:

a)\(4^x=64=4^3=>x=3\)

b)\(2^{x+1}=25=>2^x.2=25\Rightarrow2^x=25:2=12,5\)

=> ....

c)\(5^{x+2}=25\Rightarrow5^x.5^2=25=>5^x.25=25=>5^x=25:25=1\)

=>x=0

a) 

\(4^x=64\)

Ta thấy \(64=4^3\Rightarrow x=3\)

c) 

\(5^{x+2}=25\)

Ta thấy : \(25=5^2\)

Nếu \(x=1\)thì \(5^3=125\)(loại)

Nếu \(x=0\)thì \(5^{0+2}=5^2=25\)(chọn)

=> x = 0 

P/S : Phần b vừa thiếu vừa sai đề 

1.8100

2. 34 x 18 + 18 x 66

= 18 x ( 34 + 66)

= 18 x 100 = 1800

3. X × ( 8 +  12) =  160 + 20 × 12

= X x 20 = 160 + 240

= X x 20 = 400

X = 400 : 20 = 20

4. X x 12 - X x 2 = 2020

(12 - 2) x X = 2020

10 x X = 2020

X = 2020 : 10 = 202

1.8100

2. 34 x 18 + 18 x 66

= 18 x ( 34 + 66)

= 18 x 100 = 1800

3. X × ( 8 +  12) =  160 + 20 × 12

= X x 20 = 160 + 240

= X x 20 = 400

X = 400 : 20 = 20

4. X x 12 - X x 2 = 2020

(12 - 2) x X = 2020

10 x X = 2020

X = 2020 : 10 = 202