Distributeiv porpoty
a(b+c)=ab+ac
or FOIL
anyway distribute
(m-6)(m+6)=
(m-6)(m)+(m-6)(6)=
(m^2-6m)+(6m-36)=
m^2-36
One factor will be zero, hence y will be zero, when x=-3.
The other factor will be zero, hence y will be zero, when x=-5.
The zeros of the function are x ∈ {-5, -3}.
_____
This solution makes use of the "zero product rule," which states a product is zero if and only if one or more factors is zero.
When you solve that you get 30.825 because you divided 123.3 which was your dimensions times 9 and if you divide that by 4 you get 30.825 . Let me know if that is correct if not I will find new solution!
