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Write an equation for the line perpendicular to y=2x-5 through the point (8,-2)

User WillKre
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1 Answer

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For this case we have that by definition, the equation of the line of the slope-intersection form is given by:


y = mx + b

Where:

m: It is the slope of the line

b: It is the cut-off point with the y axis

By definition, if two lines are perpendicular then the product of their slopes is -1.

We have the following equation of the line:


y = 2x-5

Then
m_ {1} = 2

We find
m_ {2}:


m_ {2} = \frac {-1} {m_ {1}}\\m_ {2} = \frac {-1} {2}\\m_ {2} = - \frac {1} {2}

Thus, the perpendicular line will be of the form:


y = - \frac {1} {2} x + b

We substitute the given point and find "b":


-2 = - \frac {1} {2} (8) + b


-2 = -4 + b\\-2 + 4 = b\\b = 2

Finally, the equation is of the form:


y = - \frac {1} {2} x + 2

ANswer:


y = - \frac {1} {2} x + 2

User Kulvar
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