We are asked to find a value of 

 in which the trinomial 

 is a perfect square trinomial. The easiest way to do this is by using a method called completing the square. This method calls for taking half of the 

 term and squaring it. In this case, the 

 term is 14. When we halve it, we get 

. When we square it, we get 

. Therefore, the value of 

 in the trinomial 

 is 

.