Answer:
A
Step-by-step explanation:
Group the 4 terms into groups of 2 without changing their order. That looks like this:
[tex](2x^3+6x^2)+(5x+15)[/tex]
Now within each group pull out what's common:
[tex]2x^2(x+3)+5(x+3)[/tex]
Now we have (x + 3) common between the 2 terms, so let's pull that out. With grouping, you know that it "works" if what's in the parenthesis are both exactly the same term. Ours are both (x + 3). What's "left over" are the things we originally pulled out, so group those together and you're done!
[tex](x+3)(2x^2+5)[/tex]
