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| Question 833320:  Check my questions and answers.
 1. Does the equation represent a direct variation? If so, find the constant of variation.
 5x = -3y
 a. no
 b. yes; k = -5/3
 c. yes; k = 5/3
 d. yes; k = -3/5
 2. Does the equation represent a direct variation? If so, find the constant of variation.
 2x - 4y = 0
 a. yes; k = -4
 b. no
 c. yes; k = 1/2
 d. yes; k = -1/2
 I choose, D & B. which, I may be wrong.
 Answer by Alan3354(69443)
      (Show Source): 
You can put this solution on YOUR website! Check my questions and answers. 1. Does the equation represent a direct variation? If so, find the constant of variation.
 5x = -3y
 a. no
 b. yes; k = -5/3
 c. yes; k = 5/3
 d. yes; k = -3/5
 2. Does the equation represent a direct variation? If so, find the constant of variation.
 2x - 4y = 0
 a. yes; k = -4
 b. no
 c. yes; k = 1/2
 d. yes; k = -1/2
 I choose, D & B. which, I may be wrong.
 Dun & Bradstreet?
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 For linear equations,
 Solve for one variable in terms of the other.
 If both are in the numerator, it's direct.
 -----------
 5x = -3y
 x = -3y/5
 Direct
 --------------------
 2x - 4y = 0
 2x = 4y
 x = 2y
 Direct.
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 The constant depends on which variable you solve for.
 y is usually solved for if it's in x & y
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 x = -3y/5 --> k = -3/5
 y = -5x/3
 or y = (-5/3)x --> k = -5/3 (notice it's the reciprocal)
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 x = 2y --> k = 2
 -----
 y = x/2
 or y = (1/2)x --> k = 1/2
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 It's a poorly posed problem (not a rarity).
 Should ask for y in terms of x, or vice versa, but didn't.
 
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