Problem 1
Answer: Direct variation; k = 1/4
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Step-by-step explanation:
We can rewrite the given equation y = x/4 into y = (1/4)x. Then note how it's in the form y = kx. In this case, k = 1/4. In decimal form, this is k = 0.25
All direct variation equations are in the form y = kx. The value of k is the constant of variation.
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Problem 2
Answer: Inverse variation; k = 9
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Step-by-step explanation:
The equation 9/y = x rearranges to xy = 9.
We can then solve for y to get y = 9/x
This is in the form y = k/x, where k = 9
All inverse variation equations are in the form y = k/x, with k as the constant of variation.