ANSWER
y = -1/2x + 3
Step-by-step explanation
A line perpendicular to the given line has a slope that is opposite and reciprocal to the slope of the given line.
Let's find the slope of the line in the graph. The slope of a line passing through points (x1, y1) and (x2, y2) is,

As we can see in the graph, the line passes through points (1, 3) and (0, 1). Its slope is,

The opposite reciprocal of 2 is -1/2.
Hence, the equation of the line that is perpendicular to the line in the graph is y = -1/2x + 3.