Question

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

Answer 1

Áp dụng tính chất của dãy tỉ số bằng nhau ta có:

     \(\frac{y}{12}=\frac{x}{4}=\frac{y-x}{12-4}=\frac{4}{8}=\frac{1}{2}\)

Từ \(\frac{x}{4}=\frac{1}{2}\Rightarrow x=\frac{1}{2}.4=2\)

     \(\frac{y}{12}=\frac{1}{2}\Rightarrow y=\frac{1}{2}.12=6\)

     \(\frac{z}{15}=\frac{1}{2}\Rightarrow z=\frac{1}{2}.15=7,5\)

                      Vậy...

Answer 2

Ta có:

\(\frac{x}{4}=\frac{y}{12};y-x=4\)

\(\frac{x}{4}=\frac{y}{12}=k\)

\(\Rightarrow x=4k;y=12k\);\(z=15k\)

\(y-x=4\Rightarrow12k-4k=4\)

\(\Rightarrow\left(12-4\right)k=4\)

\(\Rightarrow8k=4\)

\(\Rightarrow k=\frac{4}{8}=\frac{1}{2}\)

\(\cdot x=4k;k=\frac{1}{2}\Rightarrow x=\frac{4.1}{2}=2\)

\(\cdot y=12k;k=\frac{1}{2}\Rightarrow y=\frac{12.1}{2}=6\)

\(\cdot z=15k;k=\frac{1}{2}\Rightarrow z=\frac{15.1}{2}=7,5\)