\(\dfrac{x+3}{x+5}=\dfrac{x-2}{x-7}\)
\(\Rightarrow\left(x+3\right)\left(x-7\right)=\left(x+5\right)\left(x-2\right)\)
\(\Rightarrow x^2+3x-7x-21=x^2+5x-2x-10\)
\(\Rightarrow x^2-4x-21=x^2+3x-10\)
\(\Rightarrow-4x-21=3x-10\)
\(\Rightarrow-4x-3x=-10+21\)
\(\Rightarrow-7x=11\)
\(\Rightarrow x=-\dfrac{11}{7}\)
Vậy \(x=-\dfrac{11}{7}\)
Tìm x, biết :
\(a.3\dfrac{4}{5}:40\dfrac{8}{15}=0,25:x\)
\(b.\left(x+1\right):\dfrac{5}{6}=20:3\)
\(c.\dfrac{7}{x-1}=\dfrac{x+1}{9}\)
Tìm x:
a) \(\dfrac{x-3}{x+5}=\dfrac{5}{7}\) b) \(\dfrac{7}{x-1}=\dfrac{x+1}{9}\)
mọi người ơi giúp mik với ai làm đc mik tick cho
Tìm x trong tỉ lệ thức
a) \(-0,52:x=-9,36:16,38\)
b) \(2\dfrac{2}{5}:x=1\dfrac{7}{9}:0,2\)
c)\(\left(\dfrac{2}{5}x\right):\dfrac{1}{3}=1\dfrac{1}{3}:\dfrac{4}{5}\)
d) \(0,3:1\dfrac{1}{3}=\dfrac{2}{5}:\left(3x+6\right)\)
e) \(\dfrac{x}{-15}=\dfrac{-60}{x}\)
f) \(\dfrac{x-1}{-15}=\dfrac{-60}{x-1}\)
g) \(\dfrac{x-1}{7}=\dfrac{9}{x+1}\)
h) \(\dfrac{x-2}{x-1}=\dfrac{x+4}{x+7}\)
Cho \(\dfrac{x}{2}=\dfrac{y}{5}=\dfrac{z}{7}\) tìm giá trị của bểu thức A= \(\dfrac{x-y+z}{x+2y-z}\)
1,2x :\(\dfrac{5}{7}\)=\(\dfrac{14}{15}\) : \(\dfrac{3}{2}\)
2,\(\dfrac{9}{10}\) :(3x) = \(\dfrac{5}{3}:\dfrac{20}{27}\)
3,\(\dfrac{x-2}{27}=\dfrac{3}{x-2}\)
4,\(\dfrac{2x+5}{9-2x}=\dfrac{2}{5}\)
5,\(\dfrac{x-7}{x+8}=\dfrac{x-8}{x+9}\)
Tìm x :
c) \(\dfrac{x+4}{20}=\dfrac{5}{x+4}\) d) \(\dfrac{x-1}{x+2}=\dfrac{x-2}{x+3}\)
mọi người ơi giúp mik với , ai làm đc mik tick cho
Tìm hai số x,y biết
a/\(\dfrac{x^3}{8}=\dfrac{y^3}{27}=\dfrac{z^3}{64};x^2+2y^2-3z^2=-650\)
b/\(\dfrac{x-1}{2}=\dfrac{y+3}{4}=\dfrac{z-5}{6};5z-3x-4y=50\)
Tìm x,y biết: \(\dfrac{x+3}{6} = \dfrac{2x + 1 }{7} = \dfrac{2 + 3x}{y}\)
dạng : tỉ lệ thức
tìm x biết
a, \(\dfrac{x-2}{-1,2}=\dfrac{-5}{2}\)
b, \(\dfrac{-6}{x+1}=\dfrac{1,8}{9}\)
c, \(\dfrac{-3}{x}=\dfrac{x}{-12}\)
d, \(\dfrac{x-4}{x-1}=\dfrac{3}{5}\)
e,\(\dfrac{1,12}{-10}=\dfrac{11,2}{x}\)
