SOLUTION: if AB is perpendicular to CD, find the valve of a if A(-2,4) B(3,5) C(-1,-3) and D(4,a)

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Question 773697: if AB is perpendicular to CD, find the valve of a if A(-2,4) B(3,5) C(-1,-3) and D(4,a)
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
Using equation for slope (m)
y2 - y1/x2 - x1
AB
5 - 4/3-(-2)
1/5
CD
a -(-3)/4 -(-1)
a + 3/5
Lines perpendicular to one
another have slopes that
multiply together to give -1
m1 * m2 = -1
1/5 * a + 3/5 = -1
a + 3/25 = -1
a + 3 = -25
a = -28
Hope this helps
:-)