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# Line D passes through the points (-2, 5) and (-1, -9). What is the slope of a line parallel to line D? A.-14 B.-1/4 C.1/14 D.14

The answer is either a,b,c or d

### 2 Answers by Expert Tutors

Tamara J. | Math Tutoring - Algebra and Calculus (all levels)Math Tutoring - Algebra and Calculus (al...
4.9 4.9 (51 lesson ratings) (51)
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Recall that the slope (m) of a line that passes through the points (x1, y1) and (x2, y2) is given by the following formula:

m = (y2 - y1)/(x2 - x1)

You are given that line D passes through the following two points:

(x1, y1) = (-2, 5)     and     (x2, y2) = (-1, -9)

Plugging in these values into the formula for the slope of a line we can solve for the slope of line D:

m = (-9 - 5)/(-1 - (-2)) = (-9 - 5)/(-1 + 2) = (-14)/(1) = -14

Thus, the slope of line D is -14.

Since parallel lines have the same slope, then the slope of a line parallel to line D has the same slope as line D. That is, any line parallel to line D will have a slope of -14.

Anthony G. | Young Math and Computer Science Expert Tutor (A Lot of Experience!)Young Math and Computer Science Expert T...
5.0 5.0 (11 lesson ratings) (11)
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For a line's slope to be parallel to line D, it has to have the SAME slope as line D has. So, just find the slope of line D and that is your answer!    To do that, just find rather rise over run,  or  (y2 - y1) / (x2-x1).   So in this case, it would be:   (-9 - 5) / (-1 -  -2)  or  (-9 + -5) / (-1 + 2). This equals  -14/1 or simply  -14. So the answer is A!