For a polynomial of the form
ax2+bx+c
, rewrite the middle term as a sum of two terms whose product is a⋅c=3⋅3=9 and whose sum is
b=10.
3x2+x+9x+3
Factor out the greatest common factor from each group.
x(3x+1)+3(3x+1)
Factor the polynomial by factoring out the greatest common factor,
3x+1.(3x+1)(x+3)
Your answer is A.