Solving a system of linear equations when the lines are parallel


Find the value of k so that the two given lines will be parallel.


First, put the two equations in standard form

3X - KY = 7

3X - 7 = KY

3X/K -7/K = Y

Now put 2X + 5Y = -1 in standard form too

2X + 1 = -5Y

2X/-5 + 1/-5 = Y

The two equations are now in standard form
y = mx + b

3X/K -7/K = Y

2X/-5 + 1/-5 = Y

They are parallel if the slope are equal.

so they are parallel if 3/K = 2/-5

Cross multiply to get

2K = -15

so K = -15/2

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Jan 11, 2014
Most regards,
by: Shah Maqsood Menatpall Akbari

Most regards to you dear sir/madam
I am so happy to be your student in mathematics.
Accept me please that will your kindness.

Thank You

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