Suppose that y varies inversely as the square of x, and that y = 8 when x = 17. What is y when x = 14? Round your answer to two decimal places if necessary.

Respuesta :

When two variables are inversely proportional we can represent them in the following manner:

[tex]y\text{ = }\frac{a}{x}[/tex]

Where "a" would be the constant of proportionality. In the case of our problem the y is inversely proportional to the square of "x", this means that the correct expression is:

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

We need to find the value of "a", to do that we will apply the ordered pair which was given to us (17,8).

[tex]\begin{gathered} 8=\frac{a}{(17)^2} \\ a=8\cdot(17)^2 \\ a=8\cdot289 \\ a=2312 \end{gathered}[/tex]

Therefore the expression to this problem is:

[tex]y=\frac{2312}{x^2}[/tex]

We want to find the value of "y" when "x" is equal to 14, therefore:

[tex]\begin{gathered} y=\frac{2312}{(14)^2} \\ y=\frac{2312}{196} \\ y=11.8 \end{gathered}[/tex]

The value of "y" is 11.8