choose equation of a line perpendicular to the given equation and passing through the point p x-axis; P =(6,2)
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To solve the question you have find the equation of the line that is perpendicular to the y axis and passes through the point (6,2), so in this case the equation of the line is y=2 as you can see in this picture
Remember that two lines are perpendicular when they form an 90 degrees angle between them