Question

3x=y ; 5y= 4z và 6x + 7y+8z =456

Answer 1

\(3x=y\)=> \(x=\frac{y}{3}\)=> \(\frac{x}{4}=\frac{y}{12}\)

\(5y=4z\)=> \(\frac{y}{4}=\frac{z}{5}\)=> \(\frac{y}{12}=\frac{z}{15}\)

=> \(\frac{x}{4}=\frac{y}{12}=\frac{z}{15}\)

=> \(\frac{6x}{24}=\frac{7y}{84}=\frac{8z}{120}=\frac{6x+7y+8z}{24+84+120}=\frac{456}{228}=2\)

<=> \(\frac{x}{4}=\frac{y}{12}=\frac{z}{15}=2\)

=> x = 2 . 4 = 8

y = 2 . 12 = 24

z = 2 . 15 = 30

KL: ........