Answer:
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Explanation:
From the graph,
The initial red incline is a straight line passing through the origin.
So, a straight line passing through the origin is of the form:

Where, 'm' is the slope.
Now, the slope of a given as the change in y value to change in x value.
Consider the two end points of the red line (0, 0) and (4, 6).
The slope with two points
on the line is given as:

Plug in
. Therefore, slope is:

Hence, the equation of the initial red incline is:
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