Question

Help needed with polynomials! Will medal!

Answer 1

can you help?

Answer 2

sure :)

Answer 3

what do you need help with?

Answer 4

first, I need help with completing a square...
for perfect square polynomials...

Answer 5

What number should be added to the expression x^2 + 4x to change it into a perfect square trinomial?

Answer 6

An example would be:

(x – 4)^2 = 5
x – 4 = ± sqrt(5)
x = 4 ± sqrt(5)
x = 4 – sqrt(5) and x = 4 + sqrt(5)

Answer 7

so with that.... since that one side is squared, you would square root both sides to cancel it out... then you would solve for x.... make sense?

Answer 8

uh... okay... so... 2*sqrt of x?

Answer 9

@MelissaHolmes well what now?

Answer 10

sorry... I got tagged again ... O.o

Answer 11

lol

Answer 12

this reply is taking you a while to type, hm?

Answer 13

so ... I put up my work on a presentation to format it... here :

Answer 14

so for this one, 4?

Answer 15

let me try-

Answer 16

ok

Answer 17

for \[x^{2}+10\] it would be 25?

Answer 18

hmmm.. is it x^2 + 10x ? or just x^2 + 10 ?

Answer 19

sorry, 10x.

Answer 20

ok, that makes more sense :)

Answer 21

botched it in the "insert equation" part

Answer 22

lol, its okay ;)

Answer 23

what about something like this-

Answer 24

Find the solution to the following equation by transforming it into a perfect square trinomial. \[x^{2}-12x=13\]

Answer 25

so you just move everything to one side:
x^2 - 12x - 13 ..... and do you think you can solve?

Answer 26

lets see...

Answer 27

well, no. 13 is prime, so how can any two numbers multiply to 13?

Answer 28

nevermind, I was simplifying to binomials.

Answer 29

I think i've got it now.

Answer 30

{-1, 13}

Answer 31

Yay!!! :D yup you got it :D

Answer 32

so that means 3x^2 + 12x = 63 would be
3x2 + 12x - 63

Answer 33

yes, and you would solve :)

Answer 34

and the solution set

Answer 35

the solution set... is
x = {3, -7} ... sound right?

Answer 36

I don't know

Answer 37

when I tried -7

Answer 38

it didn't seem to work...

Answer 39

worked this time :D

Answer 40

hmm....
did i do something wrong?

Answer 41

oh, ok :D cool :D

Answer 42

x^2 – 4x = 5 to x^2 – 4x - 5

Answer 43

then {-1, 5}, right?

Answer 44

yes!! I think you got it :D

Answer 45

NOw I have another issue-

Answer 46

quadratic formula?

Answer 47

okay, I actually like the quadratic formula more than the completing the square ....

Answer 48

so you have
\[x = frac{(-b \pm \sqrt{-b^2 - 4ac}) }{ 2a }\]

Answer 49

darn.... i messed it up...

Answer 50

but it is