Option D (The student should have used as the slope of the perpendicular line.) is correct.
Step-by-step explanation:
We need to identify the error that the student made in finding equation of the line that passes through (-8,5) and is perpendicular to y = 4x + 2
The slope of the required line would me -1/m because both lines are perpendicular.
So, slope of new line will be: -1/4
because the equation of slope-intercept form is:
where m is the slope
Now, for finding equation the student used point slope form i.e 
where y_1 and x_1 are the points and m is the slope.
Putting values:
x_1=-8, y_1=5 and m=-1/4

This is the correct solution.
The student made error by using the wrong slope he used 2 instead of -1/4
in the step 
So, Option D (The student should have used as the slope of the perpendicular line.) is correct.
Keywords: Equation of line using Slope
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