Determine the value of "n" if the lines nx - 2y + 8 = 0 and 3x + ny + 6 = 0 are PERPENDICULAR.
Now I know that the slopes of perpendicular lines are negative reciprocals of each other, but I just don't see how to set the system up to solve for "n".
jjjones42003
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First put each line into standard form:
1) y = (n/2)x + 4
2) y = -(3/n)x - 6/n
Now we see the two slopes are n/2 and -3/n. In order for them to be perpendicular, they must be negative recipricals, so we must have
n/2 = n/3 ==> n/6 = 0 ==> n = 0.
With n = 0, line 1 is horizontal and line 2 is vertical so they are perpendicular.
anordtug
Remember : the slope is tg of the angle a between x-axis and the functions line.
Then the angle between the perpendicular is tg(a+ 90 deg)= -cot a
-2y=-nx-8
y=n/2+4 is the first line (1)
ny= - 3x-6
y=-3/n- 6/n
a perpendicular to (1)
has then slope -1/(n/2)=-2/n. I cannot see that the second line can be perpendicular to (1) for any value but 0 and infinity.
?
Only because people are rude to you does not mean you have the right to insult anyone. If I am in second grade or whatever, that is not your problem. IT'S MINE. If you're not going to help then do not even comment.
By the way, I'm in college honeyyyyyyy :P
Thomas William
The same reason a 45degree slope has 12inches of rise/fall per 12inches of run, yet 6inches of fall per ft. is not 22.5 degrees
δοτζο
Just solve each for y.
y = (nx + 8)/2
y = -(3x + 6) / n