Question

Which of the following points lie in the solution set to the following system of inequalities?

y > -3x + 3
y > x + 2

(2, -5)

(-2, 5)

(2, 5)

(-2, -5)
I really need someone to walk me through because my teacher left me hanging

Answer 1

Really, all you need to do is substitute the values for each ordered pair into both inequalities and see which values give you true results for both.

For example, if we try the first ordered pair, (2, -5), substitute both of these numbers into both inequalities at the same time.

In the first inequality, you get -5> -3(2) +3 which says that -5> -6+3. Since this is false, we don't even have to substitute these numbers into the second inequality. So, the first ordered pair doesn't work. So, try the next ordered pair. If you are still having trouble, let me know.

Answer 2

How do you know what the answer is?

Answer 3

Does it come out to be true? or false?

Answer 4

You don't. You should try each of the ordered pairs into each inequality and find which ordered pair yields true statements for both inequalities. In the one I did, the ordered pair gave a false result, so it won't work. Now you have to do the rest until you find the ordered pair that gives you true results for both inequalities.

Answer 5

OK......So say if i did that ans worked it all out but what if for one of the ordered pairs i got back two different answers

Answer 6

Say One was true and the other false

Answer 7

Then the ordered pair is not a solution of the system of inequalities. The ordered pair that satisfies both inequalities at the same time will be your solution.

Answer 8

In other words, both inequalities must be true for the ordered pair you use.

Answer 9

Can you work it out with me i don't understand at all, I want to learn this because it's fun and i would love to be able to do it

Answer 10

Ok, I tried the first one. (-5, 2) gave a false result for the first inequality, so I don't even have to check the second one.

Answer 11

okay..gotcha

Answer 12

Next choice is (-2, 5). Again, check the first inequality.

5>-3(-2) )+ 3. This gives 5> 6+3 which is false. So again, I don't have to check the second inequality.

Answer 13

Do you understand what I am doing now? Try the remaining two choices.

Answer 14

kk
(2, 5)
5 > -3(2) + 3 True
5 > 2 + 2 True

Answer 15

There you go! Perfect. Since the ordered pair satisfies both, it is the solution to the problem.

Answer 16

AHHHHHHHHH OH SNAP SUGAR HONEY ICE TEA...I DID IT...

Answer 17

Okay can you help with another problem like this..

Answer 18

Fire away.

Answer 19

kk
Which of the following points lie in the solution set to the following system of inequalities?

y x - 5
y -x - 4
(1, 10)

(-1, 10)

(10, 1)

(1, -10)

Answer 20

I think you forgot some inequality symbols. This is basically the same problem as the one you just did.

Answer 21

y <= x - 5
y <=
-x - 4

Answer 22

No difference in this problem and the last problem. As long as both statements are true after substitution, the substituted ordered pair is your answer.

Answer 23

But 2 of them were false and true or true and false

Answer 24

They must both be TRUE. One true and one false, no matter the order, won't work.

Answer 25

(10, 1)

(1, -10)

these two came out like true and false

Answer 26

and the rest came out false

Answer 27

So you tried all four choices and none worked?

Answer 28

Pretty much

Answer 29

Ah, you made a typical error. On the number line, in the negative direction, the closer the number is to zero, the larger it is. One of your answer choices results in comparing two negative numbers, and I bet you decided that one negative was larger than another, when in fact, it is smaller.

Answer 30

No I actually looked over that fact so it wasn't that.

Answer 31

Hmmm...are you sure, I just did the work and found an answer choice that had two statements which were both true. And both of them involved negative numbers.

Answer 32

OHHHHHHHHHHH it was the last on..i forgot to put the negative sign on the 10 for (1,-10

Answer 33

one*

Answer 34

There you go. The last one is the correct answer.

Answer 35

감사합니다 (Thank you in Korean....).

Answer 36

You are most welcome.

Answer 37

Your awesome....You are the nicest helper on this site

Answer 38

lol...thanks, but there are many. You just have to look.