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:>?

a/ x - ( 25 - x) = x - 15

=> x - 25 + x = x - 15

=> 2x - x = -15 + 25

=> x = 10

b/ x - 8 = -13 - 8

=> x = -13 - 8 + 8 = -13

c/ x - (-15) = 5 - (-19)

=> x + 15 = 5 + 19 => x = 5 + 19 - 15 = 9

d/ (x + 35) = 2x + 15 + (13 - 4)

=> x + 35 = 2x + 15 + 13 - 4

=> x - 2x = 15 + 13 - 4 - 35

=> -x = -11 => x = 11

e/ 5 - 2x = 15-(-9) - 3x

=> 5 - 2x = 15 + 9 - 3x

=> -2x + 3x = 15 + 9 - 5

=> x = 19

g/ x + 135 = 3x - 15

=> x - 3x = -15 - 135

=> -2x = -150

=> x = -150/ - 2 = 75

`3xx4/15+2xx4/15-5xx4/15`

`=4/15xx(3+2-5)`

`=4/15xx0`

`=0`

`3 xx 4/15 + 2 xx 4/15 - 5 xx 4/15`

`= 4/15 xx (3 + 2 - 5)`

`= 4/15 xx 0`

`= 0`

\(\dfrac{15}{19}\times\dfrac{38}{5}< x< \dfrac{67}{15}+\dfrac{56}{15}\\ \Leftrightarrow6< x< 8,2\\ \Leftrightarrow x\in\left\{7;8\right\}\)

a: =10000+1025=11025

b: =15x(2+3+5)=150

\(a,\left(3416+6584\right)+1025=11025\\ b,15\times\left(2+3+5\right)=150\)

\(a,3416+1025+6584\\ =\left(3416+6584\right)+1025\\ =10000+1025\\ =11025\\ b,15\times2+15\times3+15\times5\\ =15\times\left(2+3+5\right)\\ =15\times10\\ =150\)

a,3416+1025+6584=(3416+6584)+1025=10000+1025=11025b,15×2+15×3+15×5=15×(2+3+5)=15×10=150

\(\dfrac{15}{19}\times\dfrac{38}{5}< x< \dfrac{67}{15}-\dfrac{56}{16}\\ \dfrac{5\times3\times19\times2}{19\times5}< x< \dfrac{67\times16-56\times15}{15\times16}\\ 3\times2< x< \dfrac{232}{240}\\ 6< x< \dfrac{232}{240}\) (*)

Mà : \(\dfrac{232}{240}< \dfrac{240}{240}=1\\ \)

Nên (*) là vô lí ( Do `6>232/240` )

Vậy \(x\in\varnothing\)

a: =>15/5*34/17<x<120/15

=>6<x<8

=>x=7

b; =>20/5*58/29<x<112/11

=>8<x<112/11

=>x=9 hoặc x=10