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Write the equation of a line perpendicular to y =-1/ 8x that passes through point (-12, - 4)

point slope form, thanks :) ​

Write the equation of a line perpendicular to y =-1/ 8x that passes through point-example-1
User Debbee
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1 Answer

2 votes

Answer:


y+4=3(x+12)

Explanation:

Perpendicular lines have opposite reciprocal slopes, meaning that if you had
(4)/(3), the opposite would change the sign:
-(4)/(3), and the reciprocal would flip the fraction:
(-3)/(4)

We can find the slope of the line perpendicular to the line
y=-(1)/(3)x-8 by finding the opposite reciprocal of -1/3 (slope is the coefficient of x).

  • Opposite:
    (1)/(3) Change the sign
  • Reciprocal:
    (3)/(1)=3 Flip the fraction

Now we have the slope of the line and a point that the line passes through. We are now able to use point-slope form.

Point-slope form:


  • y-y_1=m(x-x_1)

Where
(x_1, \ y_1) are the coordinates of a point that the line passes through, and
m is the slope of the line.

Substitute (-12, -4) and m = 3 into the point-slope equation.


  • y-(-4)=3(x-(-12))

Distribute the negative sign inside the parentheses.


  • y+4=3(x+12)

This is the equation of the line perpendicular to y = -1/3x - 8 and that passes through point (-12, -4) in point-slope form.

User John Giotta
by
5.2k points