Question

Which inequality does not have the solution
{x| x > 5}?

-4x<-20
6x <30
1/4x> 5/4
-3/4x< -3
I dont get it:(

Answer 1

I think its D but no sure

Answer 2

could u get solution for
-4x<-20
?
exactly where are u stuck ?

Answer 3

i need to understand how to do it

Answer 4

-4x<-20
what needs to be done to isolate x ?

Answer 5

what is {x| x > 5}?

Answer 6

ohh...
its read as 'all x, such that x greater than 5 '

Answer 7

what i dont get it

Answer 8

im so confused:(

Answer 9

You have to solve each of the four selections and see what the solution set is for each individually.

Answer 10

thats the thing whats a solution set?

Answer 11

i feel really dumb

Answer 12

When you are dealing with inequalities, and you are trying to isolate the variable, and if you need to multiply or divide by a negative number, you have to switch the sign.

Answer 13

so i solve for each one?

Answer 14

The solution set will be expressed in the form x is greater to or less than a specific number.

Yes, you solve each one and see what fits with x > 5

Answer 15

wait so the one that doesntend up withx> 5 is the on ei want right?

Answer 16

@tcarroll010 ?

Answer 17

Yes, that's right.

Answer 18

ok so i check all the problems looking for the one that does not end up with x> 5 right? just to confirm

Answer 19

For any selection, you might actually get answer of which x > 5 is a subset. In that case, x > 5 would stil be a (partial) solution, but not the whole solution

Answer 20

No, not exactly. You could get an answer where x > 5 will fit into the answer you get. x > 5 will be a solution, but will not be the total solution.

Answer 21

wait so number 2 is like this x< 5

Answer 22

is that the im looking for?

Answer 23

Looks to me like there are two solutions that would not fit the inequality.

Answer 24

For, example: If you get an answer that is x > 2, then x > 5 is a subset of x > 2 because all points in x > 5 are contained in x > 2. But the converse is not true. Not all points in x > 2 are in x > 5. Like 3 or 3.2 for example.

Answer 25

@Hero , just one. One of the answers is a superset of x > 5

Answer 26

im sorry imnot getting you what us a subset?

Answer 27

x > 5 is a subset of x > 2 because every point in x > 5 is in x > 2. In other words, if a number is greater than 5, it automatically is greater than 2.

Answer 28

i think i understand what youmean so x>10 would be the sunset of x>8?

Answer 29

Yes. The reason I went through this is that one of the answers might not have a "5" in it when you work it and you need to be able to recognize and work with a subset.

Answer 30

ok so what steps do i need to take find the answer now?

Answer 31

Solve each selection and write down the solution for that selection.

Answer 32

ok one sec

Answer 33

Yes, one of the answers is a superset, good call.

Answer 34

x>5
x<5
x>5
x<4 is that correct? thenits the fourth one right?

Answer 35

oops the second one is x>5

Answer 36

x>5
x<5
x>5
x>4

Answer 37

so its the fourth one?

Answer 38

No, it's not the fourth one.

Answer 39

the second one?

Answer 40

Is x > 5 a subset of x > 4? If it is, then x > 5 works for the fourth selection and tion is ok.

Answer 41

well then the first one then? im getting confused

Answer 42

You're just guessing now. Look at what I gave you as the full solution for each selection. Also review what a subset is. Pay special attention to my 8th and 11th replies.

Answer 43

look, i dont even know how a subset has anything to do with this i didnt learn about this in school..

Answer 44

Pay special attention to what I wrote as the full solution for each selection:
x>5
x<5
x>5
x>4

Plus, ask yourself if x > 5 is a subset of x > 4. If it is, then every point in x > 5 will work for x > 4. x > 5 will not be the WHOLE solution, but it will still be a partial solution. In other words, x > 5 will work, so selection 4 CANNOT be the answer for your question.

Subsets might not be something you learn about explicitly, but you have to be able to reason to them.

Answer 45

but what am i suppose to do with subsets?/

Answer 46

Analyze them and make a decision based on your reasoning.

Answer 47

There is only one selection that clearly stands out as the answer.

Answer 48

it looks like all of them, since they have the same numbers would all be subsets of the fourth one

Answer 49

i feel really supis cuss i dont see it...

Answer 50

The answer you are looking for is selection #2. Look again where I wrote them out. The sign is reversed. I can't explain it any easier.

Answer 51

thanks for taking the time:)

Answer 52

uw I hope you learned something here.

Answer 53

i did dont worry

Answer 54

One time, I spent two hours explaining something to a student and at the end of the explanation, the student said, "I don't get it. Can you please explain it to me again?".

Answer 55

It's the challenge of teaching and learning. Words can be conveyed but not always ideas.