SOLUTION: ``Line L, passes through points P(n, 4) and Q(1 2), Line L, passes through points R(4, 3) and S (1, 5). a) What is the value of n if the lines are parallel? b) If the lines are per

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: ``Line L, passes through points P(n, 4) and Q(1 2), Line L, passes through points R(4, 3) and S (1, 5). a) What is the value of n if the lines are parallel? b) If the lines are per      Log On


   



Question 1106594: ``Line L, passes through points P(n, 4) and Q(1 2), Line L, passes through points R(4, 3) and S (1, 5). a) What is the value of n if the lines are parallel? b) If the lines are perpendicular, what is the value of n?''.
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Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
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PQ
y-2=%28%282-4%29%2F%281-n%29%29%28x-1%29

y-2=%28-2%2F%281-n%29%29%28x-1%29

RS
y-5=%28%285-3%29%2F%281-4%29%29%28x-1%29
y-5=-%282%2F3%29%28x-1%29



(a)
Lines to be parallel?
Slopes be equal.
-2%2F%281-n%29=-2%2F3
Solve this for n.
-
1%2F%281-n%29=1%2F3
1-n=3
-n=3-1
highlight_green%28n=-2%29


(b)
Lines to be perpendicular?
-2%2F%281-n%29=3%2F2
Solve this for n.
-
cross-multiply,
-4=3%281-n%29
-4=3-3n
-4-3=-3n
3n=7
highlight_green%28n=7%2F3%29