Question

If y varies inversly as x², and y=11/4
when x=4, find y when x=2​

Answer 1

y = 11 when x = 2

Explanation:

This is indirect proportionality where:

y ∝
`(1)/(x^(2))`

This means:

`y_(1) x_(1)^(2) = y_(2)x_(2)^(2)`

Substitute the following values in the above equation to solve for
`y_(2)`

`y_(1) = (11)/(4)`

`y_(2) = ?`

`x_(1) = 4`

`x_(2) = 2`

=
`((11)/(4))(4^(2)) = y_(2)(2^(2))`

=
`((11)/(4))(16) = y_(2)(4)`

=
`44 = 4y_(2)`

=
`y_(2) =(44)/(4)`

∴ y = 11

Answer 2

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`\stackrel{\textit{`