You would multiply 4 on both sides
5x=2
then you would divide 5 on both sides
x=2/5
Given that,
The given expression is : 
To find,
The value of the above expression when x = 2 and y = 4
Solution,
We have,

Put x = 2 and y = 4 in the above expression.

So, the value of the above expression is 18.