Question

2x = 3y = 4z và x + y – z = 21

Answer 1

⇒y13=36⇒y=12⇒y13=36⇒y=12

Answer 2

Tham Thảo
https://hoc24.vn/cau-hoi/2x3y4z-va-xy-z21giup-mik-di-mik-dang-can-gap-mai-thi-roi.195645768969

Answer 3

\(2x=3y=4z\Rightarrow\dfrac{x}{\dfrac{1}{2}}=\dfrac{y}{\dfrac{1}{3}}=\dfrac{z}{\dfrac{1}{4}}\)

Áp dụng t/c dtsbn ta có:

\(\dfrac{x}{\dfrac{1}{2}}=\dfrac{y}{\dfrac{1}{3}}=\dfrac{z}{\dfrac{1}{4}}=\dfrac{x-y+z}{\dfrac{1}{2}+\dfrac{1}{3}-\dfrac{1}{4}}=\dfrac{21}{\dfrac{7}{12}}=36\)

\(\dfrac{x}{\dfrac{1}{2}}=36\Rightarrow x=18\\ \dfrac{y}{\dfrac{1}{3}}=36\Rightarrow y=12\\ \dfrac{z}{\dfrac{1}{4}}=36\Rightarrow z=9\)