ANSWER
4)x^3+ 5x^2- 9x- 45=0
EXPLANATION
Factoring by grouping is used to factor expressions that have four terms.
Among the given options, the fourth option is
[tex]x^3+ 5x^2- 9x- 45=0[/tex]
There are already four terms in this expression.
So we group the first two and the last two and factor.
We can see that x² is common to the first two terms and -5 is common to the last 2 terms.
The fourth choice is correct.
