Factor : 12x^2-24x

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Factor :  12x^2-24x  

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campbell_st · Answer

what if I write it as

$$12 \times x \times x - 2 \times 12 \times  x$$

what common factors are there...?

anonymous · Answer

Arent you supposed to write it as (6x-12)(6x+12)

campbell_st · Answer

no... it only has 2 terms so you will have a term as a factor outside a binomial 

ax(x + b) 

so what is the common factor that is outside

what's left is inside the brackets

anonymous · Answer

Oh so you would only do it my way if the two numbers didn't have a gcf, for example  if the question were 4x^2-9?

campbell_st · Answer

that's correct... its about being able o identify the type of quadratic or polynomial... 

2 terms like your 1st question is ax(bx + c)  or something in that form

this time you have 2 terms, that are both squares, and a minus... so this type is called the difference of 2 squares

$$a^2x^2 - b^2 = (ax - b)(ax + b)$$

I hope that makes sense

anonymous · Answer

Yea thanks