Manhattan Prep
Which of the following represents a line perpendicular to line k in the figure above?
$$\text{A. } 3y+2x=-12$$
$$\text{B. } 2y+x=0$$
$$\text{C. } 2y-x=0$$
$$\text{D. } y+2x=12$$
$$\text{E. } y-2x=12$$
OA D
Which of the following equations represents a line
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Hi All,
We're asked which of the 5 answers is the equation for a line that is perpendicular to line K in the figure above. This question is based on line/graphing rules.
To start, a PERPENDICULAR line is one that has an "opposite inverse" slope (sometime called a "negative reciprocal" slope). For example, if we start with a line that has a slope of 3, then a perpendicular line to that line would have a slope of -1/3.
Here, we can determine the slope of the given line... (change in Ys)/(change in Xs) = (-6 - 0)/(0 - 12) = -6/-12 = +1/2
Since the given line has a slope of +1/2, we know that the perpendicular line will have a slope of -2/1 = -2.
At this point, it would help to convert the answer choices into "slope intercept" format --> re: Y = (M)(X) + B. We need a line that begins with Y = -2X...... It shouldn't take too much work to find the one answer that fits that pattern...
Final Answer: D
GMAT assassins aren't born, they're made,
Rich
We're asked which of the 5 answers is the equation for a line that is perpendicular to line K in the figure above. This question is based on line/graphing rules.
To start, a PERPENDICULAR line is one that has an "opposite inverse" slope (sometime called a "negative reciprocal" slope). For example, if we start with a line that has a slope of 3, then a perpendicular line to that line would have a slope of -1/3.
Here, we can determine the slope of the given line... (change in Ys)/(change in Xs) = (-6 - 0)/(0 - 12) = -6/-12 = +1/2
Since the given line has a slope of +1/2, we know that the perpendicular line will have a slope of -2/1 = -2.
At this point, it would help to convert the answer choices into "slope intercept" format --> re: Y = (M)(X) + B. We need a line that begins with Y = -2X...... It shouldn't take too much work to find the one answer that fits that pattern...
Final Answer: D
GMAT assassins aren't born, they're made,
Rich