Respuesta :

Answer: When x=2 and z = 1, then the value of y =4.

Step-by-step explanation:

Given: y varies directly as x and z i.e. [tex]y\ \alpha \ xz[/tex]

[tex]y=k(xz)[/tex]      (i) , where k is the proportionality constant.

Put  Y=40 ,x =5 and z = 4, then we get

[tex]40=k(5\times4)\\\\\Rightarrow\ k=\dfrac{40}{20}\\\\\Rightarrow\ k=2[/tex]

Required equation: [tex]y=2(xz)[/tex]  [Put value of k in (i)]

Now put x=2 and z = 1, then we get

[tex]y=2(2\times1)=2(2)=4\\\\\Rightarrow\ y=4[/tex]

Hence, when x=2 and z = 1, then the value of y =4.