C

C

C

\(a,x:\left(354-293\right)=32\cdot6\\ \Leftrightarrow x:61=192\\ \Leftrightarrow x=11712\)

b, x : 65 = 36 dư 7 

\(\Rightarrow x=36\cdot65+7\\ \Leftrightarrow x=2347\)

\(c,\left(376+534\right):x=175:35\\ \Leftrightarrow910:x=5\\ \Leftrightarrow x=182\\ d,5\cdot\left(4+6x\right)=290\\ \Leftrightarrow6x+4=58\\ \Leftrightarrow6x=54\\ \Leftrightarrow x=9\)

d)5x(4+6x)=290

4a) \(\frac{x}{36}=\frac{3}{4}\)

\(\Rightarrow\frac{x}{36}=\frac{27}{36}\)

\(\Rightarrow x=27\)

4b) 33 + x = 71 - 26

33 + x = 45

x = 45 - 33

x = 12

4c) x * (3,5 + 1,5) = 10

x * 5 = 10

x = 10 ; 5 = 2

4,

\(a,\frac{x}{36}=\frac{24}{32}\)

\(=>\frac{x}{36}=\frac{3}{4}=\frac{27}{36}\)

\(=>x=27\)

\(b,71-\left(33+x\right)=26\)

\(=>-\left(33+x\right)=26-71=-45\)

\(=>33+x=45\)

\(=>x=12\)

\(c,3,5\cdot x+1,5\cdot x=10\)

\(>x\cdot\left(3,5+1,5\right)=10\)

\(=>x\cdot5=10\)

\(=>x=2\)

. là nhân nha

4. 

a) x/36 = 24/32

24/32 = 3/4 = 27/36

=> x = 27

b) 71 - ( 33 + x ) = 26

33 + x = 71 - 26

33 + x = 45

x = 45 - 33

x = 12

c) 3, 5 . X + 1, 5 . x = 10

x( 3, 5 + 1, 5 ) = 10

x . 5 = 10

x = 10 : 5

x = 2

5.

a) 4, 63 . 7, 8 + 7, 8 + 7, 8 . 4, 32

= 7, 8. ( 4, 63 + 4, 32 + 1 )

= 7, 8 . 9, 95

= 77, 61

b) 35 . 34 + 35 . 86 + 65 . 75 + 65 . 45

= 35( 34 + 86 ) + 65( 75 . 45 )

= 35 . 120 + 65 . 120

= 120 . ( 35 + 65 )

= 120 . 100

= 12 000

35 x 34 + 35 x 65 + 65 x 75 + 65 x 45

= ( 35 x 34 + 35 x 65 ) + ( 65 x 75 + 65 x 45 )

= 35 x ( 34 + 65 ) + 65 x ( 75 + 45 )

= 35 x 99 + 65 x 120

= 3465 + 7800

= 11265

\(35.34+35.65+65.75+65.45\)

=\(35.\left(34+65\right)+65.\left(75+45\right)\)

= 35. 99 +65.120

=3465 + 7800

= 11265

20,10x35-19,45x65+20,10x65-19,45x35

=(35+65)x20,10+(35+65)x19,45

=100x20,10-100x19,45

=100x(20,10-19,45)

=100x0,65=65

3,2 + 4,65 : 1,5 

=3,2+3,1

=6,3

347 + 418 + 123 + 12

=(347+123)+(418+12)

=470+430

=900

34 x 35 + 35 x 38 + 65 x 40 + 65 x 32

=35*(34+38)+65*(32+40)

=35*72+65*72

=72*(35+65)

=72*100

=7200

19 x 16 x 4 + 76 x 34

=76*16+76*34

=76*(16+34)

=76*50

=3800

136 x 68 + 16 x2 x 136 

=136*68+32*136

=136*(68+32)

=136*100

=13600

125 x 25 + 125 x 74 + 125

=125*(25+74+1)

=125*100

=12500

Tính bằng cách thuận tiện hả

3,2 + 4,65 : 1,5 = 3,2 + 3,1 = 6,3

347 + 418 + 123 + 12 = (347 + 123) + (418 + 12) = 470 + 430 = 900

34 x 35 + 35 x 38 + 65 x 40 + 65 x 32 = 35 x ( 34 + 38) + 65 x (40 + 32) = 35 x 72 + 65 x 72 = 72 x (35 + 65) = 72 x 100 = 7200

19 x 16 x 4 + 76 x 34

136 x 68 + 16 x2 x 136 

125 x 25 + 125 x 74 + 125

a) 6625 + 3525 - 25                       d) 35 x 34 + 35 x 86 + 65 x 75 + 65 x 45

= 6625 + ( 3525 -25)                     = 35 x (34 + 86 ) + 65 x (75 + 45 )

= 6625 + 3500                              = 35 x 120            + 65 x 120

= 10 125                                       = 120 x ( 35 + 65 ) 

                                                     = 120 x 100

                                                     = 12 000

a) 6625 + 3525 - 25

=10125

b) 58 x 42 + 32 x 8 + 5 x 16

= 2436 + 256 + 80

= 2772

c) (4243 + 4357 + 43) - 360 : 4

= 8643 - 360: 4

= 8642 - 90

= 8552

d) 35 x 34 + 35 x 86 + 65 x 75 + 65 x 45

= (34 +86) x 35 + (75 + 45) x 65

= 120 x 35 + 120 x 65

= 120 x (35+65)

= 120 x 100

= 12000

TL

a)    5x + 20 = 110      

<=> x = 90 : 5 = 18

 b) x + 18 = - 13 

 <=> x = - 31

  c) 120 - x =  50   

   <=> x = 70     

 d) 10 - x = -29  

     <=>  x = 39

e) - x + 31 = 61

<=> x = -30

f) -85 - x = --70

<=> x = 15

Khi nào rảnh vào kênh H-EDITOR xem vid nha!!! Thanks!

= 65 x ( 121 + 11) - 35 x ( 17 + 115 ) 

= 65 x 132 - 35 x 132 

= ( 65 - 35) x 132 

= 30 x 132 

= 3960

65x121-35x17+11x65-115x35=3.960

\(65\cdot121-35\cdot17+11\cdot65-115\cdot35\)

\(=65\cdot\left(11+121\right)-35\cdot\left(115+17\right)\)

\(=65\cdot132+35\cdot132\)

\(=132\cdot\left(65+35\right)\)

\(=132\cdot100\)

\(=13200\)