<PRE><B>Question 216060</B>
 If the line 3x+ky=8 is perpendicular to the line 2x-5y=10, what is the value of k?
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The slope m1 of 2x-5y=10 is 2/5.
The slope m2 of lines perpendicular is the negative inverse, m2 = -5/2
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The slope of 3x+ky=8 is -3/k
-3/k = -5/2
-5k = -6
k = 6/5
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