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What is an equation of the lines that passes through (-9, 12) and is perpendicular to the lines whose equation is y= 1/3x + 6

User Davor Zlotrg
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1 Answer

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12 votes

Answer:

The equation of the perpendicular line is y=-3x-15.

Step-by-step explanation:

Given the line y=1/3x+6

Comparing it with the slope-intercept form: y=mx+b


\text{Slope}=(1)/(3)

Let the slope of the perpendicular line = m

Two lines are perpendicular if the product of their slopes is -1.

Therefore:


\begin{gathered} (1)/(3)m=-1 \\ m=-3 \end{gathered}

To find the equation of the perpendicular line passing through (-9, 12), we use the point-slope form.


y-y_1=m(x-x_1)

Substituting the slope and point (-9,12), we have:


\begin{gathered} y-12=-3(x-(-9)) \\ y-12=-3(x+9) \\ y-12=-3x-27 \\ y=-3x-27+12 \\ y=-3x-15 \end{gathered}

The equation of the perpendicular line is y=-3x-15.

User Davioooh
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