Question

If y varies inversely as x and y = -3 when x = 6, how do you find x when y is 36?

Answer 1

`x=-1/2`

Explanation:

`color(blue)"Inverse"" means " 1/"variable"`

`"the initial statement is " yprop1/x`

`"to convert to an equation multiply by k, the constant of variation"`

`rArry=kxx1/x=k/x`

`"to find k, use the conditions given"`

`y=-3" when "x=6`

`y=k/xrArrk=xy=6xx-3=-18`

`"the equation is " y=(-18)/x`

`"to find x when y = 36"`

`y=(-18)/xrArrx=(-18)/y`

`rArrx=(-18)/36=-1/2`