The equation that represents the relation is y = 2x.
How to derive equation on a graph
Let's locate 2 points on the graph
consider points (2,4) and (8,16)
The equation of a line is represented as
y = mx + b
m is slope
b is y-intercept
Let's calculate slope using the two points on the graph
m = change in y/change in x
m = 16 - 4/8 - 2
= 12/6
= 2
The line passes through the origin, therefore b is zero.
Substitute into the equation of line
y = 2x + 0
y = 2x
The equation that represents the relation is y = 2x.