how do you factor 2x^2 + 4x + 18

Question

elsa213 · Answer

$\LARGE\color{blue}{2x ^2 +4x+18}$

elsa213 · Answer

That's the problem, right?

kyleighpaige · Answer

Yes that's the problem.

jiteshmeghwal9 · Answer

Split the middle term such that the product of its components is equal to 36x^2 and the sum of the components is equal to 4x

elsa213 · Answer

>.>

mathmale · Answer

I'd advise that you reduce the expression by dividing all terms by 2.  Your result?

mathmale · Answer

Unfortunately, there's ambiguity in your presentation of this problem.  If you write "2x squared," others may interpret that as (1)    (2x)^2   or as (2)    2*x^2.  Which do you mean?  Leave no doubt regarding your intentions.

bthompson361 · Answer

Use the quadratic formula $$-b + or - \sqrt{b ^{2}-4(ac)}/2a$$

bgarland2003 · Answer

Are you allowed to use the quadratic formula or do you have to factor

mathmale · Answer

As given to you:  2x^2 + 4x + 18

After factoring out the '2:'          x^2 + 2x + 9

Focus on factoring   x^2 + 2x + 9.  Suggest using the quadratic formula.  If you do, you will come up with two complex roots (such as "a + i*b").

If, strictly for example, you come up with the root      2-ib, then a factor would be 
x-2+ib.

Focus on factoring   x^2 + 2x + 9.  Suggest using the quadratic formula.

mathmale · Answer

Quadratic formula, correct version:

$$x=\frac{ -b \pm \sqrt{b^2-4ac} }{ 2a }$$

mathmale · Answer

Not quite correct, because of ambiguity in regard to what is being divided by 2a:

$$-b + or - \sqrt{b ^{2}-4(ac)}/2a$$

naka354 · Answer

2*x^2 + 4*x + 18
= 2*(x^2 + 2*x + 9)