SOLUTION: It says to complete by filling in the blank. y^2 - 13y + 36 = (y - 4)(y-___) x^2 +9x + 18 = (x+3)(x+ ____)

Algebra ->  Expressions-with-variables -> SOLUTION: It says to complete by filling in the blank. y^2 - 13y + 36 = (y - 4)(y-___) x^2 +9x + 18 = (x+3)(x+ ____)      Log On


   

Question 41439: It says to complete by filling in the blank.

y^2 - 13y + 36 = (y - 4)(y-___)

x^2 +9x + 18 = (x+3)(x+ ____)
Answer by gsmani_iyer(201) About Me  (Show Source):
You can put this solution on YOUR website!

The answers are as under:
1) %28y%5E2-13y%2B36%29 = (y-4)(y-9) Answer
2) %28x%5E2%2B9x%2B18%29 = (x+3)(x+6) Answer.

Just knowing the answers are not sufficient. You must know to solve such problems. In such problems, if the co-efficient of the first term is 1, then do as below:
1) Find out 2 such numbers product of which should be equal to the third term and the sum of the same numbers should be equal to the co-efficient of the second term i.e. middle term. Here in the first problem it is -4 and -9.
2) Verify the sum and product equals to the co-efficients of 2nd and 3rd terms respectively.
3) Now split up the middle term with those numbers as in your first example, it -4y and -9y and write it down as y%5E2-9y-4y%2B36
4) Take the first two terms and the last two terms seperately and factorise each. We get y%28y-9%29-4%28y-9%29 . Then we take the common factor i.e. (y-9)and factorise as (y-9)(y-4) i.e. taking the co-efficients of the common factor i.e. y and -4. That's all. I hope this is clear to you.
gsm