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10 votes
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Determine the value of k so that the following system has an infinite number of solutions

10x+ky= -8
-15x-6y= 12
Please help.

User Oleschri
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1 Answer

13 votes
13 votes

Answer:

k=4

Explanation:

remove x:

10x.(-3) + ky.(-3)=-8.(-3) (1)

-15x.2 - 6y.2 = 12.2 (2)

(1) - (2) => -3ky+12y = 0

<=> (12-3k)y = 0

so that y has infinitely many solutions then

12-3k = 0 => k=4

User Lakeisha
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