sqdancefan

Answer:

29. e = D/(3f²)

30. k=-4, x=41 . . . . matches the 2nd selection

Step-by-step explanation:

29. Multiply by the inverse of the coefficient of e. That coefficient is 3f², so you divide by that quantity.

... D = e(3f²)

... D/(3f²) = e . . . . . matches the first choice

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30. You want to solve for k and use it with a different y-value.

... y = kx

... -96 = k·24

... -96/24 = k = -4

For y = -164, you have

... -164 = -4·x

... -164/-4 = x = 41

The coefficient of variation is -4, x is 41.