1. \(x-8+32=68\)

\(x-8=68-32\)

\(x-8=36\)

\(x=36+8\)

\(x=44\)

_____

2. \(x+8+32=68\)

\(x+8=68-32\)

\(x+8=36\)

\(x=36-8\)

\(x=28\)

_____

3. \(98-x+34=43\)

\(98-x=43-34\)

\(98-x=9\)

\(x=98-9\)

\(x=89\)

_____

4. \(98+x-34=43\)

\(98+x=43+34\)

\(98+x=77\)

\(x=77-98\)

\(x=-21\)

_____

5. \(x:5:4=800\)

\(x:5=800.4\)

\(x:5=3200\)

\(x=3200.5\)

\(x=16000\)

_____

6. \(18+x=384:8\)

\(18+x=48\)

\(x=48-18\)

\(x=30\)

_____

7. \(\left(84,6-2\times x\right):3,02=5,1\)

\(84,6-2.x=5,1.3,02\)

\(84,6-2.x=15,402\)

\(2.x=84,6-15,402\)

\(2.x=69,198\)

\(x=69,198:2\)

\(x=34,599\)

_____

8. \(x\times5=120:6\)

\(x.5=20\)

\(x=20:5\)

\(x=4\)

_____

9. \(\left(15\times24-x\right):0,25=100:0,25\)

\(\left(15.24-x\right):0,25=400\)

\(15.24-x=400.0,25\)

\(15.24-x=100\)

\(360-x=100\)

\(x=360-100\)

\(x=260\)

1,x-8+32=68

=>x-8=68-32=36

=>x=36+8=42

2,x+8+32=68

=>x+8=68-32=36

=>x=36-8=28

3,98-x+34=43

=>98-x=43-34=9

=>x=98-9=89

4,98+x-34=43

=>98+x=43+34=77

=>x=77-98=-21

5,x:5:4=800

=>x:20=800

=>x=800x20=16000

6,18+x=384:8=48

=>x=48-18=30

7,(84,6-2x):3,02=5,1

=>84,6-2x=5,1x3,02=15,402

=>2x=84,6-15,402=69,198

=>x=69,198:2=34,599

8,5x=120:6=20

=>x=20:5=4

9,(15x24-x):0,25=100:0,25=400

=>360-x=400x0,25=100

=>x=360-100=260.

1. \(...\Rightarrow x+24=68\Rightarrow x=68-24=44\)

2. \(...\Rightarrow x+40=68\Rightarrow x=68-40=28\)

3. \(...\Rightarrow3^{2\left(8+x\right)}=9=3^2\Rightarrow2\left(8+x\right)=2\Rightarrow8+x=1\Rightarrow x=-7\)

4. \(...\Rightarrow3^{2\left(8+x\right)}=77\) (bạn xem lại đề)

5. \(...\Rightarrow x:5=800.4\Rightarrow x:5=3200\Rightarrow x=3200.5=16000\)

6. \(...\Rightarrow18+x=48\Rightarrow x=48-18=30\)

7. \(...\Rightarrow84,6-2x=5,1.3,02=15,402\Rightarrow2x=84,6-15,402\Rightarrow2x=69,198\Rightarrow x=34,599\)

8. \(...\Rightarrow5.x=20\Rightarrow x=20:5=4\)

9. \(\left(360-x\right):0,25=400\Rightarrow360-x=400.0,25=100\Rightarrow x=400-100=300\)

a: 3x=81

nên x=27

b: \(5\cdot4^x=80\)

\(\Leftrightarrow4^x=16\)

hay x=2

c: \(2^x=4^5:4^3\)

\(\Leftrightarrow2^x=2^4\)

hay x=4

Đáp án cần chọn là: C

a ) x = 5 4 x = − 5 4 b ) x = 3 2 x = − 1 2 c ) x = 3 2 x = − 1 2

d ) x = 59 40 x = 61 40 e ) x = 1 3 x = − 1 f ) x = 1 3 x = − 1

a) (x - 7) + 5 = 16

=>   x - 7 = 11

=>  x  =  18

b) 4 : x - 34 = 6

=>  4 : x = 40

=>  x  =  \(\frac{1}{10}\)

c) 120 : ( x - 1 ) + 3 = 23

=>  120 : ( x - 1 ) = 20

=>  x - 1 = 6

=>  x  = 7

d) 170 - ( x-7) : 5 = 20

=>  ( x - 7 ) : 5 = 150

=>  x - 7  = 750

=>   x   =  757

e) x + 12 + 2 .x + 3 = 4.x + 3

=>  3x + 17  = 4x  + 3

=>  x  = 15 

\(a,x-7=11\)

\(x=18\)

\(b,x-36=\frac{2}{3}\)

\(x=\frac{110}{3}\)

\(c,120:\left(x-1\right)=20\)

\(x-1=6\)

\(x=7\)

\(d,\left(x-7\right):5=150\)

\(x-7=10\)

\(x=17\)

\(d,x+12+2.x+3-4.x-3=0\)

\(x.\left(1+2-4\right)+3-3+12=0\)

\(x.\left(-1\right)+12=0\)

\(x.\left(-1\right)=-12\)

\(x=12\)

a) (x - 7) + 5 = 16

x - 7 = 16 - 5 

x - 7 = 11

x = 11 + 7

x = 18

b) 4 : x - 34 = 6

4 : x = 6 + 34

4 : x = 40

x = 4 : 40

x = 1/10

c) 120 : ( x - 1 ) + 3 =23

120 : ( x - 1 ) = 23 +3

120 : ( x - 1 ) =26

x -1 = 120 :26

x - 1 =13/60

x = 13/60 + 1

x = 73/60

d) 170 - ( x - 7 ) :5 =20

170 - ( x - 7 ) = 20:5

170 - ( x - 7 ) =4

x- 7 = 170 - 4

x - 7 = 166

x = 166 + 7

x = 173

còn câu e mik ko bt làm nhé mà k cho mik nhé

4^2 . 120 - 64 . 17 + 16 . 34

=16 . 120 - 64 . 17 + 16 . 34

=16.(120+34)-64.17

=16.154-64.17

=2464-1088

=1376

(3x + 34) - ( 7 + x ) = 186 - 120

3x + 34 - 7 - x        = 66

2x + 27                  = 66

2x                          = 66 - 27

2x                          = 39

x                            = 39 : 2             

x                            = 19,5

a, 455 456 + 234 348

b, 937 120 – 728 983

c, 234 x 34

d, 47056 : 34

a)  1376

b) 441