Question

x^2-9x+8
Polynomial expression

Answer 1

Yes it is.. :)

Answer 2

Need help

Answer 3

did u want that polynomial factored?

Answer 4

yes @ByteMe

Answer 5

First multiply 8 by x^2 and broke it down to the multiplication of two numbers which add up to -9x...

Answer 6

-3 times -3 equal -9

Answer 7

\[8x^2=-4x \qquad 2x = -6x\]\[8x^2=8x \qquad 1x = 9x\] Likewise continue till you get a sum of -9x..

Answer 8

-3 *-3=+9

Answer 9

oh okay
but dont we have to get 8

Answer 10

\[8x^2=-8x\quad-x=-9x\]

Answer 11

Use that..

Answer 12

think of two integers that :
add up to -9 and
multiply to +8

Answer 13

So you get \[\large\color{green}{x^2-8x-x+8}\]

Answer 14

That is a horrible way of solving it because it simply does not work when you are dealing with complicated functions.
Basically, you want the points were the function is 0.
So you do the following to complete the square:
\[ax^2+bx+c=0\]Multiply by 4a\[4a^2x^2+4abx+4ac=0\]Sum b^2\[4a^2x^2+4abx+4ac+b^2=b^2\]Complete the square:\[(2ax+b)^2+4ac=b^2\]\[(2ax+b)^2=b^2-4ac\]\[2ax+b=\pm \sqrt{b^2-4ac}\]\[x=\frac{-b \pm \sqrt{b^2-4ac}}{2a}\]From that you get 2 values for wich x is zero, and the factorization is:
(x-x1)(x-x2) where x1 and x2 must be the points were the function is 0.

Answer 15

Sorry, on the first line of the last paragraph I meant f is 0 not x.