Factorize:
b² - 3b - 9 = -5
[tex]\boxed{\bf{Zeroes\:are\:4\:and\:-1}}[/tex]
→ b² - 3b - 9 = -5
→ b² - 3b - 9 + 5 = 0
→ b² - 3b - 4 = 0
Now, for middle term splitting, we need to split the middle term such that
• it's sum is equal to the coefficient of b and
• it's product is equal to the product of constant term and coefficient of b².
Here,
Now, let us try to split the middle term of our equation.
→ b² - 4b + b - 4 = 0
→ b(b - 4) + 1(b - 4) = 0
→ (b - 4)(b + 1) = 0
Either:
⋆ b - 4 = 0
→ b = 4
Or:
⋆ b + 1 = 0
→ b = -1
Therefore, the two zeroes of the given equation are: 4 & -1.