tui o bít nhưng ai kb vs tui o

uk

a)x=30

b)x=65

a) x-\(\left(\frac{50x}{100}+\frac{25x}{200}\right)\)=\(11\frac{1}{4}\)

<=>x - \(\frac{1}{2}x-\frac{1}{8}x\)=\(\frac{11.4+1}{4}\)

<=>\(\frac{3}{8}x=\frac{45}{4}\)

<=>x=\(\frac{45}{4}:\frac{3}{8}\)

<=>x=30

Vậy x=30

c) (x-5).\(\frac{30}{100}\)=\(\frac{20x}{100}+5\)

<=>(x-5).\(\frac{3}{10}\)=\(\frac{x}{5}\)+5

<=>\(\frac{3x}{10}-\frac{15}{10}=\frac{x}{5}+5\)

<=>\(\frac{3x}{10}-\frac{x}{5}=5+\frac{15}{10}\)

<=>\(\frac{x}{10}=\frac{13}{2}\)

<=>x=\(\frac{13.10}{2}\)

<=>x=65

Vậy: x=65

\(c,\frac{x+1}{2}=\frac{8}{x+1}\)

\(\Rightarrow(x+1)(x+1)=2.8\)

\(\Rightarrow(x+1)^2=16\)

\(\Rightarrow(x+1)^2=4^2\)

\(\Rightarrow x+1=4\)

\(\Rightarrow x=4-1\)

\(\Rightarrow x=3\)

\(a,x-(\frac{50x}{100}+\frac{25x}{200})=11\frac{1}{4}\)

\(\Rightarrow x-\frac{50x+25x}{100}=\frac{45}{4}\)

\(\Rightarrow\frac{100x}{100}-\frac{75x}{100}=\frac{45}{4}\)

\(\Rightarrow\frac{100x-75x}{100}=\frac{1125}{100}\)

\(\Rightarrow25x=1125\)

\(\Rightarrow x=45\)

\(b,(x-5)\frac{30}{100}=\frac{200x}{100}+5\)

\(\Rightarrow\frac{30x}{100}-\frac{3}{2}=\frac{200x}{100}+5\)

\(\Rightarrow\frac{30x}{100}-\frac{200x}{100}=5+\frac{3}{2}\)

\(\Rightarrow\frac{-170x}{100}=\frac{13}{2}\)

\(\Rightarrow\frac{-170x}{100}=\frac{650}{100}\)

\(\Rightarrow-170x=650\)

\(\Rightarrow x=\frac{-65}{17}\)

ko biết

Cố đợi sang năm nhe

\(x-\left(\frac{50x}{100}+\frac{25x}{200}\right)=\frac{45}{4}\)

\(x-\left(\frac{1x}{2}+\frac{1x}{8}\right)=\frac{45}{4}\)

\(x-\left(\frac{4x}{8}+\frac{1x}{8}\right)=\frac{45}{4}\)

\(x-\frac{5x}{8}=\frac{45}{4}\)

\(\frac{8x}{8}-\frac{5x}{8}=\frac{45}{4}\)

\(\frac{3x}{8}=\frac{45}{4}\Leftrightarrow x=\frac{45}{4}:\frac{3}{8}=30\)

Vậy \(x=30\)

(x-5) x \(\frac{30}{100}\)= 200x : 100 + 5

(x-5) x \(\frac{3}{10}\)= 200x : 100 + 5

\(\frac{x.3-15}{10}\)= 2x + 5

\(\frac{x.3-15}{10}-2x=5\)

\(\frac{x.3-15}{10}-\frac{20x}{10}=5\)

\(\frac{3x-15-20x}{10}=5\)

3x - 20x - 15 = 50

-17x - 15 = 50

-17x = 65

x = 65 : -17

x = \(\frac{-65}{17}\)

a/-3/x-1

-3/x=1

x=-3

b/-4/2x-1

-2x=1

x=-1/2

c/13/x-5

13/x=5

x=13/5

d/x-(50x/100+25x/200)=45/4

x-(x/2+x/8)=45/4

x-5/8x=45/4

3/8x=45/4

x=30

e/(x-5).30/100=200x/100+5

(x-5).3/10=2x+5

3x/10-3/2=2x+5

2x-3x/10=-3/2-5

17x/10=-13/2

17x=-65

x=-65/17

f/(3x-1)/(-1/2x+5)=0

=>3x-1=0

3x=1

x=1/3

\(x-\left(\dfrac{50x}{100}+\dfrac{25x}{100}\right)=11\dfrac{1}{4}\)

\(x-\dfrac{3x}{4}=\dfrac{45}{4}\)

\(\dfrac{x}{4}=\dfrac{45}{4}\Rightarrow x=45\)

Ta có: \(x-\left(\dfrac{50x}{100}+\dfrac{25x}{200}\right)=11\dfrac{1}{4}\)

\(\Leftrightarrow x-\dfrac{1}{2}x-\dfrac{1}{8}x=\dfrac{45}{4}\)

\(\Leftrightarrow x\cdot\dfrac{3}{8}=\dfrac{45}{4}\)

hay x=30