Question

1.Find the constant of variation for the relationship f(x)= 30x.  A.10  B.30  C.x  D.f(x)


2.Find the constant of variation for the relationship shown in the following table:
 

x 1 2  3  4
y 4  8 12 16      

A. 1    B. 2    C. 3    D. 4

3.If f(x) varies directly with x, and f(x) = 8 when x = 6, write the direct linear variation equation.    A.   f(x) = x    B. f(x) = 6x    C. f(x) = 8x    D. f(x) =  x

4.If f(x) varies directly with x, and f(x) = 56 when x = 8, find the value of f(x) when x = 2    
A. 4    B. 7    C. 8    D. 14

5. Which does not show a direct variation between x and y?  
 A. y =     B. y = 2x    C. y = 0.5x    D. y = 

Answer 1

the answer is D i have this test and its the right answer for 2 reasons

1,its the only thing that looks like english

2,its always the right answer in anime logic

Answer 2

`(1)\\ f(x)=30x\ \ \ \Leftrightarrow\ \ \ (f(x))/(x) =30\ \ \ \Rightarrow\ \ \ constant=30\ \ \ \Rightarrow\ \ \ Ans.\ B.\\\\(2)\\consatnt= (y)/(x) = (4)/(1) =4\ \ \ \Rightarrow\ \ \ Ans.\ D.\\\\(3)\\f(x)=m\cdot x\ \ \ and\ \ \ f(6)=8\\\\m\cdot6=8\ \ \ \Rightarrow\ \ \ m= (8)/(6) = (4)/(3) \ \ \ \Rightarrow\ \ \ y= (4)/(3)x\ \ \ \ Ans.\ (?)`


`(4)\\f(x)=m\cdot x\ \ and\ \ f(8)=56\\\\m\cdot8=56\ \ \Leftrightarrow\ \ m= (56)/(8) =7\ \ \Rightarrow\ \ \ f(x)=7x\ \ \ \Rightarrow\ \ \ f(2)=7\cdot2=14\\\\Ans.\ D.\\\\(5)\\direct:\ \ y=m\cdot x\ \ \ and\ \ \ m\in R\\e.g.:\ \ y=2x,\ \ y=0.5x,\ \ y= (x)/(7)= (1)/(7)x,\ ...\\\\NOT\ direct:\ \ \ e.g.:\ \ y= √(x) ,\ \ y= (1)/(x),\ \ y=x^2,\ ...`