Which equation is a direct variation function?

y = x
y = 4
y = x2
y = 1/4 x + 2

Two choices are correct answer.

y = x   and y = 1/4 x

Step-by-step explanation:

We have given four equations.  

We have to choose the equations that are direct variation function.  

Direct variation function is defined as the relation where one variable vary constant times to the other variable.  

let two variables are x and y.  

y = kx   where k is constant.  

Comparing given equation , we notice that  

y = x is direct variation function where k = 1.  

y = 1/4 x is direct variation function where k = 1/4.

answer: first option i.e. 'a' is correct.

step-by-step explanation:

since we have given that

number of minutes to wrap a small gift box = 4 minutes

we need to find the number of gifts to be wrapped in 5 minutes

since there is a direct variation, as the number of minutes will increase with   number of gifts to be wrapped.

so, let the number of gifts to be wrapped in 5 minutes be x.

so, it becomes,

hence, first option 'a'   is correct.