Question

Solve the following inequalities:
a. x^2−x−6≤0
b. x^3+5x^2−4x−20>0

Answer 1

@Mertsj

Answer 2

Where are you getting all these problems? They are so wide ranging in content.

Answer 3

Factor. And remember if you multiply two factors and the product is less than 0, then 1 factor must be negative and one must be positive.

Answer 4

can you show me an example of what you mean ? @Mertsj

Answer 5

If xy is negative then either x is negative and y positive or x is positive and y is negative.

Answer 6

ok then can you do a pleaseeeeeeee @Mertsj

Answer 7

then I'll know what your talking about

Answer 8

(x-3)(x+2) is negative or 0
so x-3<0 and x+2>0 or x-3>0 and x+2<0
The first case:
x<3 and x>-2
Second case:
x>3 and x<-2
Obviously that is impossible since a number cannot be both greater than 3 and less than -2 so the answer is the first case.

Answer 9

I can't factor b @Mertsj

Answer 10

Factor x^2 out of the first 2 terms
Factor -4 out of the last 2 terms.

Answer 11

okay I did that @Mertsj

Answer 12

x^2(x+5)-4(x-5)>0

Answer 13

now what???

Answer 14

-4x-20=-4(x+5)

Answer 15

huuh

Answer 16

Where did you get -4(x-5) ???

Answer 17

x^2(x+5)-4(x-5)>0
Where did you get that?

Answer 18

factored out -4

Answer 19

Exactly my point. You did that incorrectly.

Answer 20

you said Factor -4 out of the last 2 terms

Answer 21

As I said: -4x-20=-4(x+5)

Answer 22

oh ok I put - instead +

Answer 23

So now your two terms have a common factor of x+5. Factor it out.

Answer 24

how did you get -4x-20?

Answer 25

@Mertsj

Answer 26

Perhaps you would care to read the original problem?

Answer 27

I factored it now what?

Answer 28

@Mertsj

Answer 29

The same as before. If you multiply two numbers and the answer is positive then both factors must be negative or both factors must be positive.

Answer 30

Im having trouble

Answer 31

@Mertsj

Answer 32

Write what you did so far.

Answer 33

x+5 >0

Answer 34

If you multiply two factors and the answer is positive then BOTH factors must be negative or BOTH factors must be positive.

Answer 35

so the two factors were (x+5)(x-5) ?? right

Answer 36

@Mertsj

Answer 37

Post your factored form of the polynomial.

Answer 38

I have three more questions like this, so can you just show this one to me and I'll do the other 3 on my own

Answer 39

Post your factored form of the polynomial.

Answer 40

-4(x+5)=-4(x+5)

Answer 41

You need to refactor the polynomial. The right side is 0. Keep everything else on the left.

Answer 42

-4(x+5)=0

Answer 43

If you multiply that out, it does not multiply back to the left side.
What ever you write should be the same as x^3+5x^2-4x-20

Answer 44

(-4x-20)= -4(x+5)

Answer 45

idk !!!

Answer 46

What test are you working on?

Answer 47

huuh?

Answer 48

what test

Answer 49

??

Answer 50

Where are you getting all these problems that are not related?

Answer 51

they are review questions

Answer 52

For what course?

Answer 53

math

Answer 54

What math?

Answer 55

polynomial functions unit review

Answer 56

why????

Answer 57

x^2(x+5)-4(x-5)>0

Answer 58

You posted that earlier. I pointed out that the -5 should be +5. Did you ever correct that?

Answer 59

oh yes.

Answer 60

So post the corrected version.