SOLUTION: Please help me solve this equation: Multiply. (2x^2+4x-5)(x^2+3x+3) Answers: (A) 2x^4+6x^3+13x^2-3x-15 (B) 2x^4+10x^3+13x^2-3x-15

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Question 32279: Please help me solve this equation:
Multiply. (2x^2+4x-5)(x^2+3x+3)
Answers:
(A) 2x^4+6x^3+13x^2-3x-15
(B) 2x^4+10x^3+13x^2-3x-15
(C) 2x^4+10x^3+18x^2-3x-15
(D) 2x^4+6x^3+18x^2-3x-15
The only thing I could think of to solve is FOIL but I did not get any of the answers listed. Thanks
Found 2 solutions by mukhopadhyay, mbarugel:
Answer by mukhopadhyay(490) (Show Source):
You can put this solution on YOUR website!
The coefficient of x^3 is (3*2+4*1)=10
The coefficient of x^2 is (3*2+3*4-5*1)=13
The correct answer is B

Answer by mbarugel(146) (Show Source):
You can put this solution on YOUR website!
Hello!
As you mentioned, this problem can be solved using the FOIL method. However, since there are two trinomials, it cna become a bit cumbersome. So let's do it like this. First, let's split the expression by multiplying each term in the 1st trinomial by the whole 2nd trinomial:

And then use the distributive property for each:

And finally, group like terms:

So the correct answer is B

I hope this helps!
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