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August 20, 2014

August 20, 2014

Posted by **Rachel** on Friday, January 28, 2011 at 4:09pm.

ii) If the line 7x+ky=7 is parallel to 4x-6y=-5, then what is the value of k? Answer: k = ?

- Math -
**Reiny**, Friday, January 28, 2011 at 4:37pmThe two equations are easy to solve, just add up the two equations and the y term will drop out to get

11x = 2

x = 2/11

sub back into the second (or the first) to get

7(2/11) + 6y = 7

times 11

14 + 66y = 77

66y = 63

y = 63/66 = 21/22

slope of first line = -7/k

slope of 2nd line = 4/6 = 2/3

so -7/k = 2/3

cross-multiply

2k = -21

k = -21/2

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