Question

What are the factors of 3x2 + 10x + 8?

(3x + 8)(x + 1)

(3x + 1)(x + 8)

(3x + 2)(x + 4)

(3x + 4)(x + 2)

Answer 1

(3x )(x )

You know the first terms have to be 3x and x
because only 3 and 1 give you 3

As in the problem you posted before, you need to find numbers when multiplied give you 8 and added give you 10 but taking the 3 into consideration (will change the numbers).

8 ----> 4, 2; 8,1

So by trial and error

(3x + 4) ( x + 2)
3x ^2 + 3x(2) + 4(x) + 8
3x^2 + 6x + 4x + 8
3x^2 + 10x + 8

Answer 2

So would it be (3x + 1)(x + 8)?

Answer 3

@jackellyn

Answer 4

No, it would be (3x+4)(x+2) as I showed you.

(3x+1)(x+8) would give you
3x^2 + 24x + x + 8
3x^2 + 25x + 8