Question

if y varies inversely as x and y=5 when x=2 find x when y is 4.
x=?
help

Answer 1

because y varies inversely as x,then
y=k/x,where k is a constant.
when x=2,5=k/2,k=10
y=10/x
when y=4,
4=10/x
4x=10
x=10/4=5/2