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3 years ago

3. If y varies inversely as x and y = 20 when x = 4, find y when x = 8.

Mathematics

2 answers:

miss Akunina [59]3 years ago

7 0

Answer:

y=10

Step-by-step explanation:

Y varies inversely as x means y is inversely proportional to x. Therfore :

y = k/x where k is the constant of proportionality

So to find this constant we use the scenario given.

When y is 20 x is 4. So putting these values in the equation :

y=k/x

20=k/4

k=80

Now that we have K we are can find Y when x is 8:

y=80/x

y=80/8

y=10

Vilka [71]3 years ago

4 0

Answer:

y=2

Step-by-step explanation:

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