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4. Ifline m has the equation y = 3x - 1, and line k is perpendicular to m and goes through the point (-4,3), find the equation of line k.

User Annavt
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1 Answer

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Answer:

The equation of the line k is


y=-(1)/(3)x+(5)/(3)

Step-by-step explanation:

Given that k is perpendicular to line m, defined as:

y = 3x - 1

the slope of k is the negative reciprocal of the slope of line m.

The slope of m is 3

The negative reciprocal of m is -1/3 (this is the slope of k)

Therefore, k is in the form


y=-(1)/(3)x+b

Since this line passes through the point (x, y) = (-4, 3), we can use this to obtain the value for the y-intercept, b


\begin{gathered} 3=-(1)/(3)(-4)+b \\ \\ 3=(4)/(3)+b \end{gathered}

Solving for b by subtracting 4/3 from both sides


\begin{gathered} b=3-(4)/(3) \\ \\ =(5)/(3) \end{gathered}

The equation is therefore,


y=-(1)/(3)x+(5)/(3)

User Andrew Brock
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