The polynomial is .

The general quadratic expression form is .

In the above trinomial, .Since is positive and is negative, so m and p are both negative.You need to find two negative factors with a sum of and a product of .

Make a list of the factors of 28 and look for the of factors with the sum of .

There is no factors with a sum of .So, the quadratic expression cannot be factored using integers.Therefore, is prime.

The polynomial, is prime.