Question 147455
Not quite. 
If you multiply your terms, you get 3x^2 -13x -10. Which is not what you want. You are correct in that you need 3&1 and 5&2. Now you need to find the sum of prodcuts that gives you the middle term. Notice that the sign on the constant term (10) is positive. So, the two factor must both have a + or both have a minus, in order to get a positive product.

So, start with this
(3x + A ) (x + B)
The only choices we have that allow the product of A*B to be 10 are 2,5 and 1,10.
We are trying to end up with a sum or products for the middle term that equals 11. Since there is a 3x term in one of the factors, the product can either be 3*10 + 1*1 = 31 
OR 3*1 + 1*10 = 13. Neither is 11. So the other pari of factors must be the ones we want. But in which order?
3*2 + 5+1 = 11
3*5 + 2*1 = 17
So the one we want is 3*2 and 5*1
As follows:

(3x+5)(x+2)

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