Determine whether y varies directly with x. If so, find the constant of variation k and write the
equation
x y
7 14
21 42
63 126
189 378

see explanation

Step-by-step explanation:

If y varies directly with x then the equation relating them is

y = kx ← k is the constant of variation and

k =

Check this ratio for each ordered pair, that is

k = = = = = 2

Thus k = 2 and

y = 2x ← equation of variation

options a,b,c are the right answer.

step-by-step explanation:

a linear parent function is always represented as y = x

if we write this function in the form of y=mx+c

⇒

or  

now if we plot a graph we will find these characteristics:

1) y intercept of the graph is zero so its a straight line passing through origin.

2) as we can see in both the forms of function written, values of x and y may be either positive or negative for the positive slope means points on the graph are either in first quadrant or in third one.

3) it's slope is one.

step-by-step explanation: