2x=-3y=4z
nen x/6=y/-4=z/3=k
=>x=6k; y=-4k; z=3k
1/x+1/y+1/z=3
=>1/6k+1/-4k+1/3k=3
=>1/k(1/6-1/4+1/3)=3
=>1/k=12
=>k=1/12
=>x=1/2; y=-1/3; z=1/4
1, x : y : z = 2 : 3 : 4 và x + y + z = 18
2, \(\dfrac{x}{2}=\dfrac{y}{-3}=\dfrac{z}{4}\) và 4x - 3y - 2z = 81
3, \(\dfrac{x}{3}=\dfrac{y}{2};\) 4y = 3z và x + y +z = 46
4, 5x = 3y; \(\dfrac{y}{z}=\dfrac{3}{2}\) và 2x + 3y -4z =34
Tìm x,y,z biết :
\(\dfrac{x+1}{2}=\dfrac{y+3}{4}=\dfrac{z+5}{6}\) và 2x+3y+4z=9
Tìm x,y,z, bt
a, \(\dfrac{x}{4}=\dfrac{y}{3}=\dfrac{z}{9}\&x-3y+4z=62\)
b, \(\dfrac{x}{2}=\dfrac{y}{3}=\dfrac{z}{4}\&2x+3y-5z=-21\)
c,\(\dfrac{x}{y}=\dfrac{3}{4},\dfrac{y}{z}=\dfrac{5}{7}\&2x+3y-z=186\)
d, \(2x=3y=5z\&\left|x+y-z\right|=95\)
1. tim x, y, z bt: \(\dfrac{x}{y+z+1}\)= \(\dfrac{y}{x+z+1}\)= \(\dfrac{z}{x+y-z}\)= x+y+z
2. cho \(\dfrac{4z-10y}{3}\)= \(\dfrac{10x-3z}{4}\) = \(\dfrac{3y-4x}{10}\) và 2x +3y -z=40 . tìm x, y, z
3. cho \(\dfrac{y+z}{x}\)= \(\dfrac{z+x}{y}\)= \(\dfrac{x+y}{z}\) . tinh B= ( 1+\(\dfrac{x}{y+z}\)) . (1+ \(\dfrac{y}{x+z}\)). (1+\(\dfrac{z}{x+y}\))
Tìm x,y,z biết : \(\dfrac{1}{x}\) + \(\dfrac{1}{3y}\) + \(\dfrac{1}{z}\) = \(\dfrac{1}{4}\) và 2x = 9y =4z
Tìm x,y,z trong dãy tỉ số bằng nhau
1)\(\dfrac{3x}{8}=\dfrac{3y}{64}=\dfrac{3z}{216}\)và \(2x^2+2y^2.z^2=1\)
2) \(\dfrac{2x+1}{5}=\dfrac{4y-5}{9}=\dfrac{2x+4y-4}{7x}\)
3) \(\dfrac{x^3+y^3}{6}=\dfrac{x^3-2y^3}{4}\)và x6 . y6 =14
4) \(\dfrac{x+4}{6}=\dfrac{3y-1}{8}=\dfrac{3y-x-5}{x}\)
5) \(\dfrac{3}{x-1}=\dfrac{4}{y-2}=\dfrac{5}{z-3}\)và x.y.z=192
6)\(\dfrac{x-y}{3}=\dfrac{x+y}{13}=\dfrac{x.y}{200}\)
7)\(\dfrac{x+1}{2}=\dfrac{y-1}{3}=\dfrac{z+2}{4}=\dfrac{x+y+z+2}{2x+5}\)
8) \(\dfrac{15}{x-9}=\dfrac{20}{y-12}=\dfrac{40}{z-24}\)và x.y = 1200
9)\(\dfrac{40}{x-30}=\dfrac{20}{y-15}=\dfrac{28}{z-21}\) và x.y.z = 22400
10)15x = -10y =6z và x.y.z = -30000
11) Cho\(\dfrac{x+1}{3}=\dfrac{y-2}{5}=\dfrac{2z+14}{9}\)và x+z=y
12) Cho \(\dfrac{x}{3}=\dfrac{y}{4}\)và \(\dfrac{y}{5}=\dfrac{z}{6}\).Tính M=\(\dfrac{2x+3y+4z}{3x+4y+5z}\)
\(\dfrac{x-1}{2}=\dfrac{y+3}{4}=\dfrac{z-5}{3}và5x-3y-4z=46\)
Tìm x,y,z biết:
a)\(\dfrac{2x}{3}=\dfrac{3y}{4}=\dfrac{4z}{5}\) và x + 2y+ 4z = 220
Tìm x,y,z
\(\dfrac{2x}{3}=\dfrac{3y}{4}=\dfrac{4z}{5}\) và x+y+z = 147
