\(\dfrac{4x}{-5}=\dfrac{6y}{7}=\dfrac{-3z}{8}\)
nên \(\dfrac{x}{-\dfrac{5}{4}}=\dfrac{y}{\dfrac{7}{6}}=\dfrac{z}{-\dfrac{8}{3}}\)
Áp dụng tính chất của DTSBN, ta được:
\(\dfrac{x}{-\dfrac{5}{4}}=\dfrac{y}{\dfrac{7}{6}}=\dfrac{z}{-\dfrac{8}{3}}=\dfrac{x+3y-2z}{-\dfrac{5}{4}+3\cdot\dfrac{7}{6}-2\cdot\dfrac{-8}{3}}=-36\)
=>x=45; y=-42; z=96
|x+y+z+1|=|45-42+96+1|=100
a,\(\dfrac{1+2y}{18}=\dfrac{1+4y}{24}=\dfrac{1+6y}{+6x}\)
b, \(\dfrac{1+3y}{12}=\dfrac{1+5y}{5x}=\dfrac{1+7y}{4x}\)
c,\(\dfrac{x}{z+y+1}=\dfrac{y}{x+z+1}=\dfrac{z}{x+y-2}=x+y+z\left(x,y,zkhac0\right)\)
d, \(\dfrac{3x}{8}=\dfrac{3y}{64}=\dfrac{3z}{216}va2x^2+2y^2-z^2=1\)
cho x,y,z khac 0 va\(\dfrac{x+3y-z}{z}\)= \(\dfrac{y+3z-x}{x}\)=\(\dfrac{z+3x-y}{y}\)
Tính P = \(\left(\dfrac{x}{y}+3\right)\)\(\left(\dfrac{y}{z}+3\right)\)\(\left(\dfrac{z}{x}+3\right)\)
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
a)\(\dfrac{1+3y}{12}=\dfrac{1+5y}{5x}=\dfrac{1+7y}{4x}\)
b)\((x-1)=2\left(y-2\right)=3\left(z-3\right)\)và \(2x+3y-z=50\)
c) \(\dfrac{3x-2y}{37}=\dfrac{5y-3z}{15}=\dfrac{2z-5x}{2}\) và \(10-3y-2z=-4\)
d) \(\dfrac{x-1}{2}=\dfrac{y-2}{3}=\dfrac{z-3}{4}\)và \(2x+3y-z=50\)
e) \(ab=\dfrac{1}{2};bc=\dfrac{2}{3};ac=\dfrac{3}{4}\)
f)\(\dfrac{40}{x-30}=\dfrac{20}{y-15}=\dfrac{28}{z-21}\) và \(x.y.z=22400\)
Tìm x,y,z biết
a) 3x=2y; 4x=2z& x+y+z=27
b)\(\dfrac{x}{2}\) =\(\dfrac{y}{3}\)=\(\dfrac{z}{4}\)& 2x2+3y2-5z2= -405
c) 3x=2y; 4x=2z & x+y+z=27
d) \(\dfrac{6x-3z}{5}\) =\(\dfrac{4y-6x}{7}\)=\(\dfrac{3z-4y}{9}\)& 2x+3y-5z= -21
Tìm x,y,z biết
\(\dfrac{3.\left|x\right|+5}{3}=\dfrac{3\left|y\right|-1}{5}=\dfrac{3-z}{7}\) và 2|x|+7|y|+3z=-14
Tìm x , y ,z :
a, \(\dfrac{x+z+1}{x}=\dfrac{z+x+2}{y}=\dfrac{x+y-3}{z}=\dfrac{1}{x+y+z}\)
b, 10x = 6y và \(2x^2-y^2=-28\)
c, \(\dfrac{1+2y}{18}=\dfrac{1+4y}{24}=\dfrac{1+6y}{6x}\)
d, \(\dfrac{2x+1}{5}=\dfrac{3y-2}{7}=\dfrac{2x+3y-1}{6x}\)
a,\(\left|3x-4\right|+\left|3y+5\right|=0\) b,\(\left|x+\dfrac{19}{5}\right|+\left|y+\dfrac{1890}{1975}\right|+\left|z-2004\right|=0\) c,\(\left|x+\dfrac{9}{2}\right|+\left|y+\dfrac{4}{3}\right|+\left|z+\dfrac{7}{2}\right|\le0\)
d,\(\left|x+\dfrac{3}{4}\right|+\left|y-\dfrac{1}{5}\right|+\left|x+y+z\right|=0\) e,\(\left|x+\dfrac{3}{4}\right|+\left|y-\dfrac{2}{5}\right|+\left|z+\dfrac{1}{2}\right|\le0\)
Giups mình giải bài tìm x,y,z này nhé!!! Cảm ơn nhiều ạ!!!
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=\(\dfrac{2x+3y+4z}{3x+4y+5z}\)
