Question

Factor 2x2 + 7x + 3. (2x + 2)(x + 1) (2x + 3)(x + 1) (2x + 1)(x + 3)

Answer 1

Answer:

(2x + 1)(x + 3)

Step-by-step explanation:

It is probably easier to try the answer choices than to try to factor the expression yourself.

(2x + 2)(x + 1) = 2x² +4x +2

(2x + 3)(x + 1) = 2x² +5x +3

(2x + 1)(x + 3) = 2x² +7x +3 . . . . . correct choice

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Constructed solution

If you want to factor this yourself, you can look for factors of "ac" that add to give "b". That is, you want factors of 2·3 = 6 that add up to give 7. You don't have to look very far.

... 6 = 1·6 = 2·3 . . . . . . the first factor pair adds to give 7

Now, rewrite the x term using the sum of these numbers.

... 2x² +(1 +6)x +3

... 2x +x +6x +3 . . . . eliminate parentheses

... (2x +x) +(6x +3) . . . . group pairs of terms

... x(2x +1) +3(2x +1) . . . . factor each pair

... (x +3)(2x +1) . . . . . . matches the last selection