PLEASE HELP ME TO FIND THE ANSWER OF THE FACTORISATION QUESTION GIVEN ABOVE,**2x^2-16x-18,PLEASE ANSWER THE QUESTION AS SOON AS POSSIBLE ,STEP BY STEP.**

## 2x^2-16x-18

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# 1 Answer

You can start by dividing the entire polynomial by two to reduce terms.

(2x^{2}-16x-18)/2 = x^{2}-8x-9

Now you have to find two roots whose sum is equal to -8 and whose product is equal to -9. The negative product means that they will have opposite signs. Since the factors of nine are 1,3, and 9, the answer should be obvious: +1 and -9

(x-9)(x+1) is your answer

If you look at any factorization problem in its most generic form the answer to

ax^{2}+bx + c will have two roots (sometimes a double root, and provided it has a solution)

so that if you started from:

(x+r_{1})(x+r_{2}) and multiply it out you would get

x^{2}+ r_{1}x + r_{2}x + (r_{1}*r_{2}) = x^{2} + (r_{1}+r_{2})x + (r_{1}*r_{2})

where a =1

b = (r_{1}+r_{2})

c = (r_{1}*r_{2})