Simplify the following rational expression and express in expanded form.

The solution for given expression is

Given that rational expression is:

Taking "4" as common term from denominator,

 ------- eqn 1

Let us use a algebraic identity which is as follows:

So, can be expressed as:

Substitute the above equation in eqn 1,

Cancelling (z + 2y) in numerator and denominator

Thus the solution for given expression is

1) 2/5

2) zero=0/1

3) zero=0/2

4) -4/5

5) undefined=3/0