Answer:
y = 2x
Explanation:
The graph is of a straight line through the origin. Its slope can be determined from the grid points it passes through. That slope will be the constant of proportionality for the proportion represented.
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When the graph is a line through the origin, it is a representation of a proportion that can have the equation ...
y = kx
where k is the constant of proportionality, also the slope of the line.
The value of k will be the y-value when x=1. Reading from the graph, we find the line goes through point (1, 2), so y = 2 when x = 1. That means k = 2 and the equation of the line is ...
y = 2x