Answer: x = -3
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Step-by-step explanation:
This green line goes through -3 on the x axis. Every point on this line has the same x coordinate and that x coordinate is x = -3. For instance, the two points (-3,5) and (-3,2) are on this green line. The equation of this line is x = -3 to indicate that x must be -3, but y can be anything you want. So that's why the y term doesn't even show up here. We cannot write the equation into slope intercept form. The slope of any vertical line is undefined.