Question

write the polynomial equation whose roots (zeros) are: 2, -1, 5

Answer 1

what is the comma doing there?

Answer 2

the first statment is the question. the statement after that i was wondering if that was the answer to the question.. if that makes any sense

Answer 3

oh i see
your answer should be a number
\[3x^2=12x-15\]
\[3x^2-12x+15=0\]divide by 3 get
\[x^2-4x+5=0\] then use the quadratic formula since this one will not factor using integers

Answer 4

in fact there is no real solution

Answer 5

hold the phone

Answer 6

this line
3x(x-5)-3(x-5)=0 is incorrect

Answer 7

how?

Answer 8

check
it is not what you started with

Answer 9

i have to solve by compeleting the square.. prob should have told yall that earlier

Answer 10

\[3x^2 -15x + 3x +15\neq 3x(x-5)-3(x-5)=0\]

Answer 11

it has no real solution, but we can find the complex ones and we can complete the square easily

Answer 12

ok

Answer 13

got it

Answer 14

and therefore
\[x=2\pm\sqrt{11}i\] but i am going to guess that they is a typo in the problem
look carefully and make sure that the problem you posted is the one you were given

Answer 15

Did you divide the -15 by 3?

Answer 16

oh lord a sophomore mistake

Answer 17

yes! the problem is 3x^2=12x-15

Answer 18

Jus t watchin.

Answer 19

\[x^2-4x=-5\] that is better
then \[(x-2)^2=-5+4=-1\]
\[x-2=\pm\sqrt{-1}=\pm i\]
\[x=2\pm i\]

Answer 20

i was so pleased with myself for dividing by 3 the first time i forgot the second time.
sorry

Answer 21

First time was better.

Answer 22

dont you have to move the -5 over to the otherside of the equation and make it a positive 5

Answer 23

not if you want to complete the square, no
idea is to make it look like
\[(x+b)^2=a\] and then take the square root
so best to leave the constant on the other side

Answer 24

thank you!!!!!!!! more problems though :) how do i graph the following f(x)=lx+3l

Answer 25

now teach me dont give me the answers if you can. i need to learn if ya have time

Answer 26

Do you know what "absolute value" means?

Answer 27

yes, with a calculator..

Answer 28

What you have is a absolute function f(x)=|x+3| the vertical bars on each side of the x=3 indicate the absolute value. So you could look at that like this:
y= +(x+3) and
y= -(x+3)

Answer 29

Now simply graph the following:
y=x+3 and get one line and on the same graph, graph the other value
y=-x-3.

this should be the same as x+3=y and x+3=-y.

Answer 30

There is a typo in the second post above *x=3, x+3

Answer 31

so i just draw a graph??

Answer 32

something like that