-kx/2 = -18x/k
-k^2(x)= -36x
k^2 = 36
k = 6, -6
k=6, -6 because for the lines to be parallel the slopes have to be equal.
2007-05-05 07:28:19
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answer #1
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answered by Anonymous
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lines are parallel when their slopes are equal. Put the equations in the slope y intercept form: y = mx + b. The slope m is the number in front of the x.
kx + 2y = 8 yields y= (-k/2)x + 4 yields slope = -k/2
18x + ky = 12 yelds y = (-18/k)x + 12/k yields slope = -18/k
For parallel lines: -k/ 2 = -18/k
cross multiplying we get k^2 = 36.
Therefore k = +6 and -6 (two answers). The corresponding slopes will be +3 and -3.
2007-05-05 07:27:06
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answer #2
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answered by ignoramus_the_great 7
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For the lines to parallel, their slopes have to be equal.
First convert each one to y = mx + b, where m is the slope
1. 2y = 8 - kx, y = 4 - kx/2, so the slope is -k/2
2. ky = 12 - 18x, y = 12/y - 18x/k, so the slope is -18/k
Now set the two slopes to be equal, -k/2 = -18/k, which yields -k^2 = -36, or k = 6
2007-05-05 07:31:25
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answer #3
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answered by Harlan 2
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6.
I got it this way:
kx +2y = 8
18x + ky = 12
2y = -kx + 8
ky = -18x + 12
y = -kx/2 + 4
y = -18x/k + 12
For the lines to be parallel, the slopes must be equal so:
-kx/2 = -18x/k
Get rid of the minus sign:
kx/2 = 18x/k
Multiply by 2:
kx = 36x/k
Multiply by k:
k^2 x = 36 x
Divide by x:
k^2 = 36
k = 6
2007-05-05 07:39:05
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answer #4
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answered by Anonymous
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2y = - k x + 8
y = (- k / 2).x + 4
ky = - 18 x + 12
y = ( - 18 / k).x + 12 / k
To be parallel:-
(- k/2) = (-18/k)
k/2 = 18/k
k² = 36
k = 6 (taking positive value)
2007-05-05 07:29:56
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answer #5
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answered by Como 7
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18;k=l;2
k¨2=36
k=+ or-6 answer
2007-05-05 07:29:05
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answer #6
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answered by Anonymous
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the answer to K is 23
2007-05-05 07:25:42
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answer #7
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answered by beach_babe_4321 1
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use linear method(elimination method)
2007-05-05 07:25:00
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answer #8
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answered by Tanushee a 2
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