Which of the following equations represents a line perpendicular to li

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

2 Lines will be Perpendicular if the Slopes of both results as -1

For example : m1*m2 = -1

Step 1: Find the slope from the given stem
Step 2 : Find the slope from the answer Choices

If Slopes give -1 . then that is the answer.

Answer is D

D.
Y= (1/2)x-6 is the equation of the line K. Now line perpendicular to this line should have -2 (m1*m2= -1) as the coefficient of x. Hence option D

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Slope of the line perpendicular to line k will have slope of -2
(For perpendicular lines slopes are negative reciprocal of each other)

ax+by+c = 0; where -a/b is slope.
So the calculated slope of option should be -2.
A) 3y + 2x = –12 : 2/3 Incorrect
(B) 2y + x = 0 : 1/2 Incorrect
(C) 2y – x = 0 : -1/2 Incorrect
(D) y + 2x = 12 : 2 correct, as slope is -a/b; so -1*2/1
(E) y – 2x = 12 : -2/1 Incorrect

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:

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Rich

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