To solve this problem you must identify the slope and the y-intercept and determine if they are positive or negative.
To find the slope, find two direct points on the graph and find rise over run.
This comes out to:
2/1
Since the line is pointing downward, the slope is negative.
This allows you to rule out answer choices B and C, as their slope values are positive.
Next, to find the y-intercept, you must predict, based on what is seen on the graph, where he line crosses the y-axis.
It can be assumed that the line crosses at a positive 6.
This makes your y-intercept a:
6
The answer choice that lines these up is A. y = -2x + 6