What are the factors for x squared - 18x + 8

Alright so you have

You would think to factor this that you need to find two numbers that add up to the coefficient of the middle term (-18) and multiply to the last term (8).
But this is not factorable

So to solve the equation  you have to use the quadratic formula, which is 

This polynomial is already in standard form , where a is -18, b is -18, and b is 8, so just plug the numbers into the equation.

So you get , 

Idrk but i think u should figure out the n dia n then the units it will make it way more easier