In the slope-intercept form the equation of the line L can be rewritten as y=-2x+3. The slope of line L is thus seen to be -2.

Since the product of slopes of any two perpendicular lines is -1, the slope of line perpendicular to L would be ½.

As the perpendicular line passes through the point A (-2,1), Its equation in slope-point form would be y-1 = ½ (x+2). This can written in slope intercept form also as follows:

y-= ½ x+2

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