Answer:
The multiple zero is 
.
The multiplicity is 2
Explanation:
The given function is 

To find the zero of this function, we equate it to zero.

We factor to obtain;

Observe that; the expression within the parenthesis is a perfect square.
This implies that;

This implies that;
Either 
 or 

 
 has a multiple zero which is 
 and its multplicity is 2.