Aprime polynomial is an irreducible polynomial with integer coefficients that cannot be factored into polynomials of lower degree over the real number system. which trinomial is prime? x2 – 7x – 18 x2 – 9x – 18 x2 + 3x – 18 x2 + 17x – 18

x^2 - 9x - 18

Step-by-step explanation:

x^2 - 9x - 18 is prime.

Step-by-step explanation:

x^2 - 9x - 18:

We might try to factor this: - we need 2 numbers whose product is -18 and whose sum is -9:

- 18 = 2 * -9

-18 = -2 * 9

-18 = -3 * 6

-18 = 3 * -6

-18 = -18 * 1

-18 = 18 * -1

None of these factors add up to -9 so the trinomial is prime.