Bunuel wrote:

Which of the following equations represents a line perpendicular to line k in the figure above?

(A) 3y + 2x = –12

(B) 2y + x = 0

(C) 2y – x = 0

(D) y + 2x = 12

(E) y – 2x = 12

Let’s determine the slope for line k. We see that points (12,0) and (0, -6) are on line k.

slope = change in y/change in x

slope = (-6 - 0)/(0 - 12) = -6/-12 = 1/2

The line that is perpendicular to k will have a slope of -2.

Scanning our answer choices, we see that answer choice D is correct because we can manipulate that equation to read y = -2x + 12.

Answer: D

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Jeffery Miller

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