How do you factor $3x^2+7x+2$ ?

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Answer 1 · 2016-07-11T21:00:36

$3x^2+7x+2=(x+2)(3x+1)$

$3x^2+7x+2=(x+2)(3x+1)$

Answer 2 · 2016-07-11T21:36:38

$(3x+1)(x+2)$

Both 3 and 2 are prime numbers, so there are not many options..

We need the factors of 3 and 2 which add together to make 7.
All the signsare positive.

$3 = 3 xx1 and 2 = 2 xx 1$
The only possible combinations are:

$3xx1 + 1xx2 = 3+2 = 5 " wrong combination"$
$3xx2 +1xx1 = 6+1 = 7 " right combination"$

Choose factors and cross multiply to get 7.

$" 3 1" rArr 1xx1 = 1$
$" 1 2" rArr 3xx2 =6$ 6+1 = 7

The top row is the one bracket.
The bottom row is the other bracket.
$(3x+1)(x+2)$

Verify that these are correct by multiplying out the brackets.

How do you factor 3x^2+7x+2 3x^2+7x+2?