Sum/Difference of 2 monomials is (in simplest terms) a monomial when the 2 monomials are 'like terms
(1,0) or (2,5) or (3,10)
5-0=5, 10-5=5, and 15-10=5
If - 1 is a zero then

is a factor.
Dividing with this factor using the long division approach, we get the quadratic factor to be,

(see attachment).
We can rewrite the polynomial as

We can further factor as

That is
Answer:
Move all terms to the left side and set equal to zero. Then set each factor equal to zero.
b
= M
/4 + 9
x