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18 votes
18 votes
Write the equation of a line PERPENDICULAR to the line y = 3x + 2 that passes through

the point (9, -2)

User Drewsmits
by
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1 Answer

23 votes
23 votes

Answer:
y = -1/3x + 1

Explanation:

1) For a perpendicular line, the slope is the opposite reciprocal. What this means is that, the slope will be the opposite sign and flipped.

~-1/3 will be the new slope

2) Then you have to rewrite the problem using the point slope form which is y - y1 = m(x-x1). The values that we will be plugging in for x1 and y1 will be from the coordinate that you provided.

~ y - (-2) = -1/3(x-9)

3) Now simplify everything you can
~y+2 = -1/3(x-9)

4) Now distribute the -1/3
~y+2 = -1/3x + (9)(1/3)
~y+2 = -1/3x + 3

5) Now we need to subtract 2 from both sides to get y by itself.

~y = -1/3x + 1

User DavidTonarini
by
2.8k points