Question

giúp tớ

Answer 1

`3/7 + (-5/2) + (-3/5)`

`=3/7 - 5/2 - 3/5`

`=30/70 - 175/70 - 52/70`

`=(30-175-52)/70`

`=-197/70`

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`4/5 - (-2/7) -7/10`

`=4/5 + 2/7 -7/10`

`=56/70 + 20/70 - 49/70`

`=(56+20-49)/70`

`=-13/70`

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`3/8 . 19 1/3 - 3/8 -33 1/3`

`= 3/8 . 58/3 - 3/8 . 100/3`

`=3/8 . (58/3 - 100/3)`

`=3/8 . (-42)/3`

`=3/8 . (-14)`

`=-21/4`

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`(-2/3)^3 .`\(\sqrt{81}+\dfrac{4}{3}\)

`=-8/27 . 9 + 4/3`

`=-8/3 + 4/3`

`=(-8+4)/3`

`=-4/3`

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\(\dfrac{4}{5}.\left(\dfrac{7}{2}+\dfrac{1}{4}\right)^2\)

`=4/5 . ( 14/4 + 1/4)^2`

`=4/5 . ((14+1)/4)62`

`=4/5 . (15/4)62`

`=4/5 . 225/16`

`=45/4`

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\(\dfrac{15}{34}+\dfrac{7}{21}+\dfrac{19}{34}-\dfrac{20}{15}+\dfrac{3}{7}\)

`=15/34 + 1/3 + 19/34 -4/3 + 3/7`

`=(15/34 + 19/34) + (1/4-4/3)+3/7`

`=34/34 + (-3/3) + 3/7`

`=1+(-1)+3/7`

`=0+3/7`

`=3/7`

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\(\left|-\dfrac{5}{2}\right|+3^5:3^2\)

\(=\left|-\dfrac{5}{2}\right|+3^{5-2}\)

\(=\left|-\dfrac{5}{2}\right|+3^3\)

\(=\left|-\dfrac{5}{2}\right|+27\)

`=5/2 + 27`

`=59/2`

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\(12,5:\left(-\dfrac{7}{5}\right)+1,5:\left(-\dfrac{7}{5}\right)\)

`=12,5 xx (-5/7) + 1,5 xx (-5/7)`

`=(-5/7) xx (12,5 + 1,5)`

`=(-5)/7 xx 14`

`=-10`

Answer 2

`x + 1/2 = 2^5 : 2^3`

`x+1/2=`\(2^{5-3}\)

`x+1/2=2^2`

`x+1/2=4`

`x=4-1/2`

`x=8/2-1/2`

`x=7/2`

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`x/2 = 3/4`

`x = 3/4 xx 2`

`x=6/4`

`x=3/2`

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`56-4x=100`

`4x=56-100`

`4x=-44`

`x=-44:4`

`x=-11`

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`1/3x : 2/3 = 1 3/4 : 2/5`

`1/3 x : 2/3 = 7/4 : 2/5`

`1/3 x : 2/3 =7/4 xx 5/2`

`1/3 x : 2/3 = 35/8`

`1/3 x = 5/8 xx 2/3`

`1/3 x = 35/12`

`x=35/12:1/3`

`x=35/12 xx 3`

`x=35/4`

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\(\left(-\dfrac{2}{3}\right)^2.x=\left(-\dfrac{2}{3}\right)^5\)

`x =(-2/3)^5 : (-2/3)^2`

\(x=\left(-\dfrac{2}{3}\right)^{5-2}\)

`x=(-2/3)^3`

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`x/2 = 8/x`

`x.x=2.8`

`x.x=16`

`x^2=16`

\(x=\left(\pm4\right)^2\)

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`|x+5|-6=9`

`|x+5|=9+6`

`|x+5|=15`

`@TH1:`

`x+5=15`

`x=15-5`

`x=20`

`@TH2:`

`x+5=-15`

`x=-15-5`

`x=-20`

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\(2^x+2^{x+3}=144\)

\(2^x.\left(1+2^3\right)=144\)

2^x.9=144`

`2^x = 144 :9`

`2^x = 16`

`2^x  =2^4`

`=> x = 4`