If y varies inversely as x^2 and y = 3 when x = 18, what is y when x = 3?a. 6 b .108 c.54 d.27 Please select the best answer from the choices provided ABCD

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Riia

It is given in the question that

y varies inversely as x^2 and y = 3 when x = 18.

SInce y varies inversely as square of x, so the formula will be

[tex]y = \frac{k}{x^2}[/tex]

Where k is the constant of proportionality .

Substituting the values of y and x, we will get

[tex]3 = \frac{k}{18^2}[/tex]

[tex]3 = \frac{k}{324}[/tex]

Multiplying both sides by 324,

[tex]k = 972[/tex]

So the equation will be

[tex]y= \frac{972}{x^2}[/tex]

And when x equals 3, we will get

[tex]y = \frac{972}{9} = 108[/tex]

Therefore the correct option is B .