Áp dụng tính chất dãy tỉ số bàng nhau ta có:
\(\frac{x}{2}\)=\(\frac{y}{3}\)=\(\frac{z}{4}\)=> \(\frac{x^2}{2^2}\)=\(\frac{y^2}{3^2}\)=\(\frac{z^2}{4^2}\)=\(\frac{x^2+y^2+z^2}{2^2+3^2+4^2}\)=\(\frac{110}{29}\)
=> x = 2 . \(\frac{110}{29}\)=\(\frac{220}{29}\)=\(7\frac{17}{29}\)
=> y = 3. \(\frac{110}{29}\)= \(\frac{330}{29}\)=\(11\frac{11}{29}\)
=> z = 4. \(\frac{110}{29}\)=\(\frac{440}{29}\)=\(15\frac{5}{29}\)
Vậy x, y, z lần lượt bằng: ......
Tim cac so x,y,z biet \(\frac{x}{5}=\frac{y}{7}=\frac{z}{3}\)va x2 va y2 va z2
tim x, y, z biet
1. \(\frac{x+y}{2015}=\frac{xy}{2016}=\frac{x-y}{2017}\)
2.\(\frac{2x+2}{3}=\frac{3y-1}{4}=\frac{4x+2}{5}\)va x+y+z=7
tim x , y, z biet,\(\frac{z}{4}=\frac{y}{3};\frac{x}{2}=\frac{z}{5}\) va x+y+z=51
Tim x,y,z biet
a,5x= 8y= 20z va x-y-z = 3
b,\(\frac{6}{11}x=\frac{9}{2}y=\frac{18}{5}z\)va -x+y+z =120
c,\(\frac{x}{12}=\frac{y}{9}=\frac{z}{5}\)va x . y . z =20
d,\(\frac{x}{5}=\frac{y}{7}=\frac{z}{3}\)va \(^{x^2+y^2-z^2}\)=585
Tim x,y,z, biet:
a)\(\frac{x}{5}=\frac{y}{6};\frac{y}{2}=\frac{z}{3}\)va \(x^3-2.x^2.y+z^3\)
b) \(2x=4y=5z\)va \(2x-3y-z=1\)
TIM X, Y ,Z , BIET :\(\frac{x-2}{6}=\frac{y+3}{9}=\frac{z-7}{10}\)va \(x+y+z=106\)
tim x y z biet \(\frac{x-4}{2}\)=\(\frac{y-6}{3}\)=\(\frac{z-8}{4}\)va x+y+z=27
Tim x,y,z :
a) x=y:2,\(\frac{y}{4}=\frac{z}{5}\)va 2x+2y-z-7=0
b)\(\frac{1}{2}x=\frac{2}{3}y=\frac{3}{4}z\)va x-y=15
c)\(\frac{x}{y}=\frac{2}{3}\), \(\frac{x}{z}=\frac{1}{2}\)va \(x^3\)- xyz=-16
tim x,y,z biet:
\(\frac{x}{2}\)=\(\frac{y}{3}\); \(\frac{y}{2}\)=\(\frac{z}{5}\); va x+y-3z=2
