\(42-3\cdot\left(17-x\right)-3=?\)

a) 

<=> 219 - 7x - 7 = 100

<=>         -7x       = 100 - 219 + 7

<=>          -7x      = -112

<=>             x       = -112 : (-7)

<=>             x       = 16

b)

<=> 9x - 18 = 34

<=> 9x         = 34 + 18

<=> 9x         = 52

<=>   x         = 52 : 9

<=>   x         = 52/9

a)219-7(x+1)=100

         7(x+1)=219-100

         7(x+1)=119

            x+1 =119:7

            x+1 =17

            x     =17-1

            x     =16

b)  (3x-6).3=34

    3x-6      =34:3

    3x-6      =\(\frac{34}{3}\)

    3x         =\(\frac{34}{3}\)- 6

    3x         =\(\frac{16}{3}\)

      x         =\(\frac{16}{3}\): 3

      x         =\(\frac{16}{9}\)

ko bit ai         dung

a) x – 32 : 16 = 48 ó x – 2 = 48 ó x = 48 + 2 ó x = 50

b) 88 – 3.(7+x) = 64 ó 3.(7+x) = 88 – 64 ó 7 + x = 24:3 ó x = 8 – 7 ó x = 1

c) (5+4x) : 3 – 121 : 11 = 4 ó (5+4x) : 3 – 11 = 4 ó (5+4x) : 3 = 4 + 11 ó 5+4x = 15.3 ó 4x = 45 – 5 ó 4x = 40 ó x = 10

d) 15 – 2(3x+1) = 11.13 – 130 ó 15 – 2(3x+1) = 143 – 130 ó 15 – 2(3x+1) = 13

ó 2(3x+1) = 15 – 13 ó 3x + 1 = 2:2 ó 3x = 1 – 1 ó 3x = 0 ó x = 0

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

\(\Rightarrow x+2-2=0\)

\(\Rightarrow x=0\)

\(\left(x+3\right)+1=7\)

\(\Rightarrow x+3+1=7\)

\(\Rightarrow x+4=7\)

\(\Rightarrow x=3\)

\(\left(3x-4\right)+4=12\)
\(\Rightarrow3x-4+4=12\)

\(\Rightarrow3x=12\)

\(\Rightarrow x=4\)

\(\left(5x+4\right)-1=13\)

\(\Rightarrow5x+4-1=13\)

\(\Rightarrow5x+3=13\)

\(\Rightarrow5x=10\)

\(\Rightarrow x=2\)

\(\left(4x-8\right)-3=5\)

\(\Rightarrow4x-8-3=5\)

\(\Rightarrow4x-11=5\)

\(\Rightarrow4x=16\)

\(\Rightarrow x=4\)

\(8-\left(2x+4\right)=2\)

\(\Rightarrow8-2x-4=2\)

\(\Rightarrow4-2x=2\)

\(\Rightarrow2x=2\)

\(\Rightarrow x=1\)

\(7+\left(5x+2\right)=14\)

\(\Rightarrow7+5x+2=14\)

\(\Rightarrow9+5x=14\)

\(\Rightarrow5x=5\)

\(\Rightarrow x=1\)

\(5-\left(3x-11\right)=1\)

\(\Rightarrow5-3x+11=1\)

\(\Rightarrow16-3x=1\)

\(\Rightarrow3x=15\)

\(\Rightarrow x=5\)

a)219-7(x+1)=100

7(x+1)=219-100

7(x+1)=119

x+1=119:7

x+1=17

x=17-1

x=16

b)(3x-6).3=3⁴

(3x-6).3=81

3x-6=81:3

3x-6=17

3x=27+6

3x=33

x=33:3

x=11

li-ke cho mình nha Duong Thi Hoai My

(3x-6).3= 3 mũ 4

nếu gì nguyện cau chúc củat bai t0an va thay s0 thi  sa0

a. 219 - 7(x+1) = 100

    7(x+1)=119

     x+1=119:7

    x+1=17

    x=16

Vậy x=16

b. (3x - 6) . 3 = 3⁴

     3x-6=3⁴:3

     3x-6=3³

     3x=33

    x=11

Vậy x=11  

a) \(219-7\left(x+1\right)=100\)

\(\Leftrightarrow219-7x-7=100\)

\(\Leftrightarrow-7x=100-219+7=-112\)

\(\Leftrightarrow x=16\)

b) \(\left(3x-6\right)\cdot3=3^4\)

\(\Leftrightarrow\left(x-2\right)\cdot3^2=3^4\)

\(\Leftrightarrow x-2=3^2\)

\(\Leftrightarrow x=9+2=11\)

a) \(219-7\left(x+1\right)=100\)

\(\Rightarrow7\left(x+1\right)=119\)

\(\Rightarrow x+1=119:7\)

\(\Rightarrow x+1=17\)

\(\Rightarrow x=16\)

b) \(\left(3x-6\right)3=3^4\)

\(\Rightarrow\left(3x-6\right)=3^3:3\)

\(\Rightarrow\left(3x-6\right)=3^3\)

\(\Rightarrow\left(3x-6\right)=27\)

\(\Rightarrow3x=27-6\)

\(\Rightarrow3x=21\)

\(x=21:3\)

\(\Rightarrow x=7\)

a) 2011 : { 639 : [ 316 – ( 78 + 25 )] : 3 }

= 2011 : { 639 : [ 316 – 103 ] : 3}

= 2011 : ( 639 : 213 : 3 ) = 2011 : (3 : 3 ) = 2011 : 1 = 2011

b) ( 3x –   2 3   )   .   7   =   7 4

3x – 8 =  7 4 : 7

3x – 8 =  7 3

3x – 8 = 343

3x = 343 + 8

3x = 351

x = 351 : 3 = 117

c) (8705 + 5235) – 5x = 3885

13940 – 5x = 3885

5x = 13940 – 3885

5x = 10055

x = 10055 : 5 = 2011

b,Ta có 3x+7:x-2=>3x-6+13:x-2=>3(x-2)+13:x-2=>13:x-2

Vì \(x\in N\Rightarrow x-2\in N\Rightarrow x-2\inƯ\left(13\right)=\left(1,13\right)\Rightarrow x\in\left(3,15\right)\)

a) (3x-15)⁷ = 0

3x-15 = 0

3x = 0+15

3x = 15

x = 15:3

x = 5

b) 4^2x-6 = 1

<=> 2x-6 = 0

2x = 0+6

2x = 6

x = 6:2

x = 3

a) (3x-15)⁷ = 0

3x-15 = 0

3x = 0+15

3x = 15

x = 15:3

x = 5

b) 4^{2x - 6} = 1

<=> 2x-6 = 0

2x = 0+6

2x = 6

x = 6:2

x = 3