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If y varies directly with x, and x = -6 when y = 2 and how do you find x when y = -9?

Answer 1

Genesis Allen

#x= 27#

#y prop x or y = k*x ; k# is variation constant

#x=-6 ; y=2 :. 2= k* (-6) or k = 2/-6 or k = -1/3#

Thus,the variation equation becomes #y = -1/3 x or x=-3y#

When #y=-9 :. x =-3*y or x=-3* -9 =27#

#x= 27# [Ans]

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Answer 2

Julia Adams

To find x when y = -9, you can use the direct variation formula:

(y = kx)

First, solve for the constant of variation (k) using the given data point (x = -6, y = 2):

(2 = k \times (-6))

(k = \frac{2}{-6} = -\frac{1}{3})

Now that you have the value of (k), substitute it into the direct variation formula along with the given value of y:

(-9 = -\frac{1}{3}x)

To solve for x, multiply both sides by (-3):

(-9 \times -3 = x)

(27 = x)

So, when y = -9, x = 27.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.