Question

các bác ơi , giúp tuii vs 

Answer 1

e.

$\frac{8}{23}.\frac{46}{24}=\frac{1}{3}x$

$\frac{2}{3}=\frac{1}{3}x$

$x=\frac{2}{3}: \frac{1}{3}=2$

f.

$\frac{1}{5}:x=\frac{1}{5}-\frac{1}{7}=\frac{2}{35}$

$x=\frac{1}{5}: \frac{2}{35}=\frac{7}{2}$

g.

$\frac{4}{9}-(x-\frac{1}{2})^2=\frac{1}{3}$

$(x-\frac{1}{2})^2=\frac{4}{9}-\frac{1}{3}=\frac{1}{9}=(\frac{1}{3})^2=(\frac{-1}{3})^2$

$\Rightarrow x-\frac{1}{2}=\frac{1}{3}$ hoặc $x-\frac{1}{2}=\frac{-1}{3}$
$\Rightarrow x=\frac{1}{3}+\frac{1}{2}=\frac{5}{6}$ hoặc $x=\frac{-1}{3}+\frac{1}{2}=\frac{1}{6}$

h.

$3,2x-(\frac{4}{5}+\frac{2}{3}):3\frac{2}{3}=\frac{7}{20}$

$3,2x-\frac{2}{5}=\frac{7}{20}$

$3,2x=\frac{7}{20}+\frac{2}{5}=\frac{3}{4}$

$x=\frac{3}{4}: 3,2=\frac{15}{64}$

i.

$(4\frac{1}{2}-2x).1\frac{4}{61}=6\frac{1}{2}$

$(\frac{9}{2}-2x).\frac{65}{61}=\frac{13}{2}$

$\frac{9}{2}-2x=\frac{13}{2}: \frac{65}{61}=\frac{61}{10}$

$2x=\frac{9}{2}-\frac{61}{10}=\frac{-8}{5}$

$x=\frac{-8}{5}:2 =\frac{-4}{5}$

Answer 2

a.

$\frac{5}{7}-\frac{3}{7}x=1$

$\frac{3}{7}x=\frac{5}{7}-1=\frac{-2}{7}$

$x=\frac{-2}{7}: \frac{3}{7}=\frac{-3}{2}$

b.

$x-\frac{-3}{4}=\frac{-14}{25}$

$x=\frac{-14}{25}+\frac{-3}{4}=\frac{-131}{100}$

c.

$\frac{-5}{20}-x=\frac{-7}{5}$

$x=\frac{-5}{20}-\frac{-7}{5}=\frac{23}{20}$

d.

$x+\frac{3}{4}=\frac{36}{144}.\frac{-12}{9}=\frac{-1}{3}$
$x=\frac{-1}{3}-\frac{3}{4}=\frac{-13}{12}$

 

Answer 3

a: =>3/7x=-2/7

=>x=-2/3

b: =>x=-14/25+3/4=-56/100+75/100=21/100

c: =>-1/4-x=-7/5

=>x+1/4=7/5

=>x=7/5-1/4=28/20-5/20=23/20

d: =>x+3/4=1/4*(-4/3)=-1/3

=>x=-1/3-3/4=-4/12-9/12=-13/12

e: =>x*1/3=46/23*8/24=2*1/3=2/3

=>x=2

f: =>1/5:x=2/35

=>x=1/5:2/35=1/5*35/2=35/10=7/2

g: =>(x-1/2)^2=4/9-1/3=1/9

=>x-1/2=1/3 hoặc x-1/2=-1/3

=>x=5/6 hoặc x=-1/6

h: =>3,2x=3/4

=>16/5x=3/4

=>x=3/4:16/5=3/4*5/16=15/64

i: =>(4,5-2x)=6,1

=>2x=-1,6

=>x=-0,8