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Suppose y varies inversely with x. How do you write an equation for the inverse variation for Y = 5 when x = -5?

Answer 1

The equation for the inverse variation is y = k/x, where k is the constant of variation. To find the value of k, substitute the given values of y and x into the equation and solve for k. In this case, when y = 5 and x = -5, the equation becomes 5 = k/(-5). Solving for k, we get k = -25. Therefore, the equation for the inverse variation is y = -25/x.

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Answer 2

Eva Adamson

#" "y=(-25)/x#

As #x# increases the #y# decreases.

#=> y->1/x" "#

#1/x # becomes smaller as #x# becomes bigger.

To complete this picture we need a constant

Let the constant be #k#

Then

#y" "=" "kxx1/x" " =" " k/x#

We are told that when #y=5" ; "x=-5#

So we have

#y=k/x" " ->" " 5=k/(-5)#

So # k=(+5)xx(-5) = -25#

Thus the equation becomes:#" "y=(-25)/x#

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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.