Question

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

y less than or equal to x - 5
y greater than or equal to -x - 4

(-5, 2)

(5, -2)

(-5, -2)

(5, 2)

Answer 1

@amistre64 @Callisto @phi

Answer 2

@AravindG

Answer 3

Did you graph them and found the solution region?

Answer 4

No, How would I do that?

Answer 5

use graph paper
graph the lines y=x-5 and y=-x-4

Answer 6

yep

Answer 7

find the region below or on the line y=x-5 and above or on the line y=-x-4

Answer 8

you could also use a graphing calculator

Answer 9

Here is one :
http://my.hrw.com/math06_07/nsmedia/tools/Graph_Calculator/graphCalc.html

Answer 10

I'm in a library, so I don't have graphing paper, and I have no clue how to use a graphing calculator. :/

Answer 11

its easy just plugin the quations in boxes y1 and y2

Answer 12

*equations

Answer 13

Okay. I'll try it right now;

Answer 14

or go to https://www.desmos.com/calculator and type in the two equations
(copy and paste works too)

Answer 15

How do I make a less than or equal too sign on the graphing calculator?

Answer 16

you don't need to, just graph the line and remember you are looking at the region less than or equal to it

Answer 17

In my calculator click on the square having equal to after the y1 or y2

Answer 18

I'm so confused > . <

Answer 19

in desmos, enter the less than sign then the equals sign
<= or >=

Answer 20

Okay, I'm gonna use desmos then.

Answer 21

ok.

Answer 22

I did it. What next?

Answer 23

you typed in both your equations?

Answer 24

Yes.

Answer 25

look at where your four points are

Answer 26

see which one satisfies both inequalities

Answer 27

0,5 and -4,5

Answer 28

@Peter14

Answer 29

i woulda just plugged in the 4 points to see what made true results

Answer 30

(-5, 2)

is 2 <= -5 - 5 true?
is 2 >= --5 - 4 true?


(5, -2)

is -2 <= 5 - 5 true?
is -2 >= -5 - 4 true?


(-5, -2)

is -2 <= -5 - 5 true?
is -2 >= --5 - 4 true?


(5, 2)

is 2 <= 5 - 5 true?
is 2 >= -5 - 4 true?

Answer 31

Oh, okay! @amistre64 I'll try that,

Answer 32

it is nice to know that other stuff, but it takes way to much time when taking a test.

Answer 33

It's -5, -2, right?

Answer 34

(-5, -2)

-2 <= 0 true
-2 >= 1 false

not that one

Answer 35

well, -10 up top, but still false :)

Answer 36

So, it's -5, something right?

Answer 37

dunno, lets try another one

(5, -2)

-2 <= 5 - 5
-2 <= 0 true

-2 >= -5 - 4
-2 >= -9 true

that fits nicely

Answer 38

Awesome. Thanks :)