SOLUTION: I am having a hard time understanding constants. Here is my problem: Determine the constant k so that the graph of 3x+(k-1)y=k+1 will have slope 5. Thank you.

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Question 67471: I am having a hard time understanding constants. Here is my problem: Determine the constant k so that the graph of 3x+(k-1)y=k+1 will have slope 5.
Thank you.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
I am having a hard time understanding constants. Here is my problem: Determine the constant k so that the graph of 3x+(k-1)y=k+1 will have slope 5.
:
Arrange the equation in the point/intercept form, y = mx + b
:
(k-1)y = -3x + (k+1)
:
The problem wants the slope (m) to = 5. This can be accomplished by dividing the
coefficient of x, (-3) by the coefficient of y,(k-1)
:
Find the value of k which will give us a slope of 5:
5 = -3/(k-1)
5(k-1) = -3
5k - 5 = -3
5k = -3 + 4
5k = +2
k = 2/5
k = +.4
:
Substitute .4 for k:
(.4-1)y = -3x + (.4+1)
-.6y = -3x + 1.4
y = (-3/-.6)x + (1.4/-.6)
y = +5x - 2.33
:
The graph:
+graph%28+300%2C+200%2C+-4%2C+4%2C+-10%2C+10%2C+5x+-+2.33%29+
:
Note that it has a slope of +5
:
Did this make sense to you?