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Assume y varies inversely as #x," if " y=7 " when " x=6#, how do you find y when #x=-12#?

Answer 1

To find y when x=-12, we can use the inverse variation equation. First, we can set up the equation as y = k/x, where k is the constant of variation. To find the value of k, we can substitute the given values of y and x into the equation. When y=7 and x=6, we have 7 = k/6. Solving for k, we get k = 42. Now, we can substitute the value of k and the new value of x into the equation to find y. When x=-12, we have y = 42/(-12). Simplifying this expression, we find y = -3.

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Answer 2

Avery Alexander

#y = -3.5#

Write the information as in inverse proportion first.

#y prop 1/x#

Make an equation by multiplying by the constant #k#

#y = k/x" "rArr k = xy#

Find the value for #k# from the information given.

#k = 6 xx7 = 42#

#:. y= 42/x#

Now find the required value of #y#:

#y = 42/-12#

#y = -3.5#

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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.