5-2x = 3x -20
5+20 = 2x + 3x
25 = 5x
x = 25 : 5
x = 5
b) ( x - 2/5 ) : 9/10 = 5/3
x- 2/5 = 5/3 . 9/10
x- 2/5 = 1
x = 1 + 2/5
x = 7/5
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Các câu hỏi tương tự
Tìm x, biết:
a) \(\frac{x}{5}-\frac{x}{6}=\frac{3}{10}\)
b) \(-1\frac{5}{27}-\left(3x-\frac{7}{9}\right)^3=-\frac{24}{27}\)
1. thực hiện phép tính
B 5frac{3}{5}.left(0,5right)^2+left(frac{8}{5}-25%right):4frac{1}{4}
2.tính nhanh
a.2frac{1}{9}.14frac{2}{5}-2frac{1}{9}.5frac{2}{5} b) -1,7 .2,3.+1,7+(-3,7)-1,7 .3-0,17:0,1
3. tìm x
a) x-30% xfrac{1}{2} b)left(3frac{1}{2}+2xright):1frac{5}{7}2frac{1}{3}
Đọc tiếp
1. thực hiện phép tính
B= \(5\frac{3}{5}.\left(0,5\right)^2+\left(\frac{8}{5}-25\%\right):4\frac{1}{4}\)
2.tính nhanh
a.\(2\frac{1}{9}.14\frac{2}{5}-2\frac{1}{9}.5\frac{2}{5}\) b) -1,7 .2,3.+1,7+(-3,7)-1,7 .3-0,17:0,1
3. tìm x
a) x-30% x=\(\frac{1}{2}\) b)\(\left(3\frac{1}{2}+2x\right):1\frac{5}{7}=2\frac{1}{3}\)
Tìm x, biết:
a, \(\left(2\dfrac{3}{4}-1\dfrac{4}{5}\right)x=1\)
b, \(x^2-9\) \(3-5x=0\)
c, \(\left|3x-1\right|+2\dfrac{3}{4}=3\dfrac{1}{16}\)
e)\(\dfrac{7}{10}\cdot\dfrac{-3}{5}+\dfrac{7}{10}\cdot\dfrac{-2}{5}-\dfrac{3}{10}\)
f)\(\dfrac{-3}{7}\cdot\dfrac{5}{9}+\dfrac{4}{9}\cdot\dfrac{-3}{7}+2\dfrac{3}{7}\)
g)
\(\dfrac{5}{9}\cdot\dfrac{10}{17}+\dfrac{5}{9}\cdot\dfrac{9}{17}-\dfrac{5}{9}\cdot\dfrac{2}{17}\)
Mn giúp em với ạ
a,frac{2}{3}x-frac{1}{2}frac{1}{10} ;b,5frac{4}{7}:x13 ;c,left(2frac{4}{5}x-50right):frac{2}{3}51
d,frac{2}{3}+frac{1}{3}:xfrac{3}{5} ;e,8frac{2}{3}:x-10-8
g,x+30%x-1,3 ;i,3frac{1}{3}x+16frac{3}{4}-13,25
k,left(2frac{4}{5}x-50right):frac{2}{3}51 ;m,/2x-1/left(-4^2right)
Đọc tiếp
\(a,\frac{2}{3}x-\frac{1}{2}=\frac{1}{10}\) ;\(b,5\frac{4}{7}:x=13\) ;\(c,\left(2\frac{4}{5}x-50\right):\frac{2}{3}=51\)
\(d,\frac{2}{3}+\frac{1}{3}:x=\frac{3}{5}\) ;\(e,8\frac{2}{3}:x-10=-8\)
\(g,x+30\%x=-1,3\) ;\(i,3\frac{1}{3}x+16\frac{3}{4}=-13,25\)
\(k,\left(2\frac{4}{5}x-50\right):\frac{2}{3}=51\) ;m,/2x-1/=\(\left(-4^2\right)\)
x/2=5/7
3x+1/3=4x-5/5
1-3x/5x+2=1/2
(2 mũ x-1) (1/3x=5/4)=0
a,frac{3}{4}-x1 b,x+4frac{1}{5} c,x-frac{1}{5}2
d,x+frac{5}{3}frac{1}{81} e,x-frac{10}{3}frac{7}{15}.frac{3}{5} g,x+frac{3}{22}frac{27}{121}.frac{11}{9}
h,1-xfrac{49}{65}.frac{5}{7} i,frac{8}{23}.frac{46}{24}-xfrac{1}{3} k,frac{62}{7}.xfrac{29}{9}:frac{3}{56}
Đọc tiếp
\(a,\frac{3}{4}-x=1\) \(b,x+4=\frac{1}{5}\) \(c,x-\frac{1}{5}=2\)
\(d,x+\frac{5}{3}=\frac{1}{81}\) \(e,x-\frac{10}{3}=\frac{7}{15}.\frac{3}{5}\) \(g,x+\frac{3}{22}=\frac{27}{121}.\frac{11}{9}\)
\(h,1-x=\frac{49}{65}.\frac{5}{7}\) \(i,\frac{8}{23}.\frac{46}{24}-x=\frac{1}{3}\) \(k,\frac{62}{7}.x=\frac{29}{9}:\frac{3}{56}\)
Ai giúp mình bài này với:
a) -5/9+ 3/5- 3/9+ -2/5
b) (1/9- 9/17)+ 3/6- (12/7- 1/2)+ 5/9
tính
a) (2dfrac{5}{6}+1dfrac{4}{9}):(10dfrac{1}{12}-9dfrac{1}{2})
b) dfrac{0,8:left(dfrac{4}{5}:1,25right)}{0,64-dfrac{1}{25}}
c) dfrac{left(100-dfrac{2}{25}right):dfrac{4}{7}}{left(6dfrac{5}{9}-3dfrac{1}{4}right).2dfrac{2}{27}} + (1,2 . 0,5) : dfrac{3}{5}
Đọc tiếp
tính
a) (\(2\dfrac{5}{6}+1\dfrac{4}{9}\)):(\(10\dfrac{1}{12}\)-9\(\dfrac{1}{2}\))
b) \(\dfrac{0,8:\left(\dfrac{4}{5}:1,25\right)}{0,64-\dfrac{1}{25}}\)
c) \(\dfrac{\left(100-\dfrac{2}{25}\right):\dfrac{4}{7}}{\left(6\dfrac{5}{9}-3\dfrac{1}{4}\right).2\dfrac{2}{27}}\) + (1,2 . 0,5) : \(\dfrac{3}{5}\)