x=50

k mik nha

^_^

Học tốt

x-{150-[30+20.(100:20)]}=30

x={150-[30+20.5]}=30

x={150-[20+100]}=30

x={150-120}=30

x=30

Vậy x=30

x - { 150 - [30 + 20 . ( 100.20 )}} = 30

X = {150 - [30 + 20 . 5 ]} = 30

X= [150 - 130 ] = 30

X - 20 = 30 

x = 30 + 20 

X = 50

XONG RÙI K MÌNH NHA 

a)50 + x = 180 - 120

 50 + x = 60

 x = 60-50 

 x = 10

b)20-x = 150-140

 20-x = 10

x = 20-10

x = 10

c) 25+x = 100-40

25+x=60

x= 60-25

x=35

d) 100+x =130-25

100+x = 105

x = 105-100

x = 5

e) 143+x = 174-22

143+x = 152

x = 152-143

x = 9 

ỦNG HỘ MK NHÁ

120 + ( 50 + x ) = 180

50 + x = 180 - 120

50 + x = 60

x = 60 - 50

x = 10

140 + ( 20 - x ) = 150

20 - x = 150 - 140

20 - x = 10

x = 20 - 10

x = 10

100 - ( 25 + x ) = 40

25 + x = 100 - 40

25 + x = 60

x = 60 - 25

x = 35

130 - ( 100 + x ) = 25

100 + x = 130 - 25

100 + x = 105

x = 105 - 100

x = 5

174 - ( 143 + x ) = 22

143 + x = 174 - 22

143 + x = 152

x = 152 - 143

x = 9

k mk nha 

Thanks nhìu

\(120+\left(50+x\right)=180\)

\(\Rightarrow50+x=180-120\)

\(\Rightarrow50+x=60\)

\(\Rightarrow x=60-50=10\)

Vậy x = 10

\(140+\left(20-x\right)=150\)

\(\Rightarrow20-x=150-140\)

\(\Rightarrow20-x=10\)

\(\Rightarrow x=20-10=10\)

Vậy x =x10

\(100-\left(25+x\right)=40\)

\(\Rightarrow25+x=100-40\)

\(\Rightarrow25+x=60\)

\(\Rightarrow x=60-25=35\)

Vậy x = 35

\(130-\left(100+x\right)=25\)

\(\Rightarrow100+x=130-25\)

\(\Rightarrow100+x=105\)

\(\Rightarrow x=105-100=5\)

Vậy x = 5

\(174-\left(143+x\right)=22\)

\(\Rightarrow143+x=174-22\)

\(\Rightarrow143+x=152\)

\(\Rightarrow x=152-143=9\)

Vậy x = 9

a)\(\frac{1}{2}x+\frac{9}{4}-\frac{8}{20}=\frac{77}{20}\)

<=>\(\frac{1}{2}x=\frac{77}{20}-\frac{9}{4}+\frac{8}{20}=\frac{77-45+8}{20}\)

<=>\(\frac{1}{2}x=\frac{40}{20}=2\)

<=>\(x=2:\frac{1}{2}=2.2\)

<=>x=4

                     Vậy x=4

\(\frac{100\left(x+20\right)}{x\left(x+20\right)}-\frac{100x}{x\left(x+20\right)}=\frac{1}{3}\)

\(\frac{100x+2000-100x}{x\left(x+20\right)}=\frac{1}{3}\)

\(\frac{2000}{x\left(x+20\right)}=\frac{1}{3}\)

\(\Rightarrow x^2+20x=3.2000\)

\(\Rightarrow x^2+20x-6000=0\)

ĐKXĐ: \(x\ne0;x\ne-2\)

Ta có: \(\frac{100x+2000-100x}{x\left(x+20\right)}=\frac{1}{3}\)

\(\Leftrightarrow\frac{2000}{x^2+20x}=\frac{1}{3}\)

\(\Leftrightarrow x^2+20x=6000\)

\(\Leftrightarrow x^2+2.10x+100=6100\)

\(\Leftrightarrow\left(x+10\right)^2=6100\)

\(\Leftrightarrow\orbr{\begin{cases}x=10\sqrt{61}-10\left(TM\right)\\x=-10\sqrt{61}-10\left(TM\right)\end{cases}}\)

Vậy...

b)\(\frac{28}{100}x+\frac{4}{25}+\frac{10}{4}=\frac{203}{50}\)

<=>\(\frac{28}{100}x=\frac{203}{50}-\frac{10}{4}-\frac{4}{25}=\frac{406-250-16}{100}\)

<=>\(\frac{28}{100}x=\frac{140}{100}\)

<=>\(x=\frac{140}{100}:\frac{28}{100}=\frac{140}{100}.\frac{100}{28}\)

<=>x=5

a) \(\frac{1}{2}x+\frac{9}{4}-\frac{8}{20}=\frac{77}{20}\)

=>  \(\frac{1}{2}x=\frac{77}{20}+\frac{8}{20}-\frac{9}{4}=2\)

=>  \(\frac{x}{2}=2\Rightarrow x=2\cdot2=4\)

vậy x = 4

b) \(\frac{28}{100}x+\frac{4}{25}+\frac{10}{4}=\frac{203}{50}\)

=>  \(\frac{28}{100}x=\frac{203}{50}-\frac{10}{4}-\frac{4}{25}=1\frac{2}{5}=\frac{7}{5}\)

=> \(\frac{28x}{100}=\frac{7}{5}\Rightarrow28x=\frac{100\cdot7}{5}=140\Rightarrow x=140:28=5\)

vậy x = 5

c)  \(\frac{100}{58}=\frac{1}{2}x\)

=>  \(\frac{100}{58}=\frac{x}{2}\Rightarrow x=\frac{100\cdot2}{58}=3\frac{13}{29}=\frac{100}{29}\)

vậy x = 100/29

(4,53 x 02+6,165 x 3):2,5

=(0,906  + 18,495); 2,5

=19,401: 2,5

=7,7604

trả lời 

=259 

chúc bn 

hc tốt

100:4+5-10-5+50+46+4-120+240+295-150-55+20-150+100=259

Chúc học tốt!!!!!!!!

trả lời 

=295 

chúc bn 

hc tốt

Ta có: \(\left(x+20\right)^{100}\ge0;\left|y+4\right|\ge0\)

Mà \(\left(x+20\right)^{100}+\left|y+4\right|=0\)

\(\Rightarrow x+20=0\text{ và }y+4=0\)

\(\Rightarrow x=-20\text{ và }y=-4\)

Vậy...