Given that y varies directly as x and inversely as 2m-1 and that y = 5 when x=7and m=4, calculate of variation k

Inverse variation can be represented as:

y

=

k

x

k

=

y

.

x

where

k

is the constant

x

=

7

and

y

=

10

so,

k

=

7

*

10

=

70

Now, we have the value of

k

and

x

=

10

, substituting these in the variation to find

y

k

=

y

.

x

y

=

k

x

y

=

70

10

=

7

on observing the values

when

x

=

7

,

y

=

10

, and

when

x

=

10

,

y

=

3

as the value of

x

decreases

y

increases and vice verse as they vary inversely.