Given that (x+3) is a factor of 6x^3 - bx^2 + 18, find the value of b.

-16=b

Step-by-step explanation:

If x+3 is a factor of 6x^3 - bx^2 + 18, then 6(-3)^3-b(-3)^2+18=0.

That's called factor theorem.

Let's solve.

First simplify what we can.

6(-27)-b(9)+18=0

-162-9b+18=0

Combine like terms:

-144-9b=0

Add 9b on both sides:

-144=9b

Divide both sides by 9:

-144/9=b

-16=b