x=-36

x=11

x=100

x=14

x=-36

x=11

x=100

x=14

2: \(\Leftrightarrow\left(\dfrac{x+1}{12}-1\right)+\left(\dfrac{x+2}{13}-1\right)=\left(\dfrac{x+3}{14}-1\right)+\left(\dfrac{x+4}{15}-1\right)\)

=>x-11=0

=>x=11

3: \(\Leftrightarrow\left(\dfrac{x-85}{15}-1\right)+\left(\dfrac{x-74}{13}-2\right)+\left(\dfrac{x-67}{11}-3\right)+\left(\dfrac{x-64}{9}-4\right)=0\)

=>x-100=0

=>x=100

\(3^x\times2+15=33\)

\(3^x\times2=33-15\)

\(3^x\times2=18\)

\(3^x=18:2\)

\(3^x=9\)

\(3^x=3^2\)

\(\Rightarrow x=2\)

Vậy \(x=2\)

3x×2+15=33

3�×2=33−153x×2=33−15

3�×2=183x×2=18

3�=18:23x=18:2

3�=93x=9

3�=323x=32

$\Rightarrow x=2$

Vậy $x=2$

\(2^3x+5^2x=2.\left(5^2+2^3\right)-33\)

\(8x+25x=2.\left(25+8\right)-33\)

\(8x+25x=2.33-33\)

\(8x+25x=66-33\)

\(8x+25x=33\)

\(x+\left(8+25\right)=33\)

\(x+33=33\)

\(x=0\)

\(15:\left(x+2\right)=\left(3^3+3\right):10\)

\(15:\left(x+2\right)=\left(27+3\right):10\)

\(15:\left(x+2\right)=30:10\)

\(15:\left(x+2\right)=3\)

\(x+2=15:3\)

\(x+2=5\)

\(x=3\)

Ta có: \(15:\left(x+2\right)=\left(3^3+3\right):10\)

\(\Leftrightarrow15:\left(x+2\right)=3\)

\(\Leftrightarrow x+2=5\)

hay x=3

\(\Leftrightarrow3^x\cdot2=18\)

hay x=2

3^x=33-15

3^x=18

3^x=18:2

3^x=9

Mà 9=3^2 nên x=2

15: ( x +2 ) = ( 3³ +3 ) : 10

15:(x+2)=3

x+2=5

x=3

\(\dfrac{15}{x+2}=\dfrac{3^3+3}{10}\\ \Leftrightarrow\dfrac{15}{x+2}=\dfrac{27+3}{10}\\ \Leftrightarrow\dfrac{15}{x+2}=\dfrac{30}{10}\\ \Leftrightarrow\dfrac{15}{x+2}=3\\ \Leftrightarrow x+2=\dfrac{15}{3}\\ \Leftrightarrow x+2=5\\ \Leftrightarrow x=5-2\\ \Leftrightarrow x=3\)

20-[7.(x-3)+4]=2

x=5

3^x.2+15=33

x=2

4/15 +1/2=23/30
51/9 - 2/3=5
3/4 x 15/26=45/104

7/3 : 5/14=98/15

4/15 + 1/2

= 8/30 + 15/30

= 23/30

51/9 - 2/3

= 51/9 - 6/9

= 45/9

= 5

3/4 × 15/26

= 45/104

7/3 : 5/14

= 7/3 × 14/5

= 98/15

a) x + 10 = 20

<=> x = 20 - 10 = 10

Vậy x = 10

b) 2x + 15 = 35

<=> 2x = 35 - 15 = 20

<=> x = 10

Vậy x = 10

c) 3(x + 2) = 15

<=> x + 2 = 15 : 3 = 5

<=> x = 5 - 2 = 3

Vậy x = 3

d) 10x + 15.11 = 20.10

<=> 10x + 165 = 200

<=> 10x = 200 - 165 = 35

<=> x = 35 : 10 = 3,5

Vậy x = 3,5

e) 4(x + 2) = 3.4

<=> x + 2 = 3

<=> x = 3 - 2 = 1

Vậy x = 1

f) 33x + 135 = 26.9

<=> 33x + 135 = 234

<=> 33x = 234 - 135 = 99

<=> x = 99 : 33 = 3

Vậy x = 3

g) 2x + 15 + 16 + 17 = 100

<=> 2x + 48 = 100

<=> 2x = 100 - 48 = 52

<=> x = 52 : 2 = 26

Vậy x = 26

h) 2(x + 9 + 10 + 11) = 4.12.5

<=> x + 30 = 120

<=> x = 120 - 30 = 90

Vậy x = 90