Ta có:

36 x 12 + 36 x 14 + 36 x 28

= 36 x (12+14+28)

= 36 x 54

= 1944

Đ/s :1944

=36*(12+14+28)   mik ko viết lại đề bài nữa

=36*54

=1944

36 x 12 + 36 x 14 + 36 x 28

= 36 x (12 +14 +28)

= 36 x 54

=1944

Đáp án là C

⇒ B C N N ( 12 , 28 , 36 ) = 2 2 . 3 2 . 7 = 252

⇒ B C ( 12 , 28 , 36 ) = B ( 252 ) = 0 , 252 , 504 , …

v ì   150 < x < 300 ⇒ x = 252

x-36=28x12

x-36=336

x=336+36

x= 372

a) 45 x 76 + 90 x 12

= 45 x 76 + 45 x 2 x 12

= 45 x 76 + 45 x 24

= 45 x ( 76 + 24 ) 

= 45 x 100

= 4500

b) 2 x 31 x 12 + 4 x 6 x 69

= 24 x 31 + 24 x 69

= 24 x ( 31 + 69 )

= 24 x 100

= 2400

c) 36 x 28 + 36 x 82 + 64 x 69 + 64 x41

= 36 x ( 28 + 82 ) + 64 x ( 69 + 41 )

= 36 x 110 + 64 x 110

= 110 x ( 36 + 64 )

= 110 x 100

= 11 000

d) 156 ( x + 61)  = 82

=> x + 61 = \(\frac{82}{156}\)

=> x + 61 = \(\frac{41}{78}\)

=> x = \(\frac{41}{78}\)- 61

=> x = \(\frac{-4717}{78}\)

45 x 76 + 90 x 12 = 45 x 76 + 45 x 2 x 12

= 45 x 76 + 45 x 24

= 45 x (76 + 24)

= 45 x 100 

= 4500

b) 2 x 31 x 12 + 4 x  6 x 69 = 62 x 12 + 2 x 12 x 69

= 62 x 12 + 138 x 12

= (62 + 138) x 12

= 200 x 12 = 2400

a, 45 x 76 + 90 x 12

= ( 45 x 12 ) + ( 76 x 90 )

=  540     +   6840

=     7 380

c,

= 36 x ( 28 + 82 ) +  64 x ( 69 + 41 )

= 36 x  110    +   64 x 110

= 110 x ( 36 + 64 )

= 110 x 100

= 11000

a.

\(10-2\left(4-3x\right)=-4\)

\(\Leftrightarrow2\left(4-3x\right)=10+4\)

\(\Leftrightarrow2\left(4-3x\right)=14\)

\(\Leftrightarrow4-3x=7\)

\(\Leftrightarrow3x=-3\)

\(\Leftrightarrow x=-1\)

b.

\(-12+3\left(-x+7\right)=-18\)

\(\Leftrightarrow3\left(-x+7\right)=-18+12=-6\)

\(\Leftrightarrow-x+7=-6:3=-2\)

\(\Leftrightarrow x=9\)

c.

\(-45:5.\left(-3-2x\right)=3\)

\(\Leftrightarrow-9.\left(-3-2x\right)=3\)

\(\Leftrightarrow-3-2x=-\dfrac{1}{3}\)

\(\Leftrightarrow2x=-\dfrac{8}{3}\)

\(\Leftrightarrow x=-\dfrac{4}{3}\notin Z\left(loại\right)\)

Câu này em ghi sai đề?

d.

\(3x-28=x+36\)

\(\Leftrightarrow2x=28+36\)

\(\Leftrightarrow2x=64\)

\(\Leftrightarrow x=32\)

e.

\(\left(-12\right)^2.x=56+10.13x\)

\(\Leftrightarrow144x=56+130x\)

\(\Leftrightarrow144x-130x=56\)

\(\Leftrightarrow14x=56\)

\(\Leftrightarrow x=4\)

B; 36 x 28 + 36 x 82 + 64 x 69 + 64 x 41

= 36 x (28+82) + 64 x (69 + 41)

= 36 x 110 + 64 x 110

= (36+64) x 110

= 100 x 110

= 11000

b) 36 nhan ( 28+82) + 64 nhan ( 69 + 41)

= 36. 110 + 64 . 110

= 110 . ( 36 + 64 )

= 110 .100

=11000

a) 2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3

= 24 x 31 + 24 x 42 + 24 x 27

= 21 x ( 31 + 42 + 27)

= 21 x 100

= 2100

b) 36 x 28 + 36 x 82 + 64 x 69 + 64 x 41

= 36 x ( 28 + 82) + 64 x ( 69 + 41)

= 36 x 110 + 64 x 110 

= 110 x ( 36 + 64)

= 110 x 100

= 11000

a)2 x 31 x12 + 4 x 6 x 42 + 8 x 27 x 3

= 24 x 31 + 24 x 42 + 24 x 27

= 24 x (31 + 24 + 27)

=24 x 82

=1968

b)36 x 28 + 36 x 82 + 64 x 69 + 64 x 41

=36 x (28 + 82) + 64 x ( 69 + 41 )

=36 x 110 + 64 x 110

=3960 + 7040

=11000

a) 2x31x12+4x6x42+8x27x3

=2x12x31+4x6x42+8x3x27

=24x31+24x42+24x27

=24x(31+42+27)

24x100=2400

b)36x28+36x82+64x69+64x41

=36x(28+82)+64x(69+41)

=36x110+64x110

a) \(58+7x=100\)

\(=>7x=100-58\)

\(=>7x=42\)

\(=>x=42:7\)

\(=>x=6\)

b) \(3x-7=28\)

\(=>3x=28+7\)

\(=>3x=35\)

\(=>x=35:3\)

\(=>x=\dfrac{35}{3}\)

c) \(x-56:4=16\)

\(=>x-14=16\)

\(=>x=16+14\)

\(=>x=30\)

d) \(101+\left(36-4x\right)=105\)

\(=>36-4x=105-101\)

\(=>36-4x=4\)

\(=>4x=36-4\)

\(=>4x=32\)

\(=>x=32:4\)

\(=>x=8\)

e) \(\left(x-12\right):12=12\)

\(=>x-12=12.12\)

\(=>x-12=144\)

\(=>x=144-12\)

\(=>x=132\)

f) \(\left(3x-2^4\right).7^3=2.7^4\)

\(=>3x-2^4=2.7^4:7^3\)

\(=>3x-16=2.7=14\)

\(=>3x=14+16\)

\(=>3x=30\)

\(=>x=30:3\)

\(=>x=10\)

i) \(\left(10+2x\right).4^{2011}=4^{2013}\)

\(=>10+2x=4^{2013}:4^{2011}\)

\(=>10+2x=4^2=16\)

\(=>2x=16-10\)

\(=>2x=6\)

\(=>x=6:2\)

\(=>x=3\)

\(#WendyDang\)