## unheard 2 years ago 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)

1. unheard

@amistre64 @Callisto @phi

2. unheard

@AravindG

3. AravindG

Did you graph them and found the solution region?

4. unheard

No, How would I do that?

5. Peter14

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

6. AravindG

yep

7. Peter14

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

8. AravindG

you could also use a graphing calculator

9. AravindG
10. unheard

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

11. AravindG

its easy just plugin the quations in boxes y1 and y2

12. AravindG

*equations

13. unheard

Okay. I'll try it right now;

14. Peter14

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

15. unheard

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

16. Peter14

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

17. AravindG

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

18. unheard

I'm so confused > . <

19. Peter14

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

20. unheard

Okay, I'm gonna use desmos then.

21. AravindG

ok.

22. unheard

I did it. What next?

23. Peter14

you typed in both your equations?

24. unheard

Yes.

25. Peter14

look at where your four points are

26. Peter14

see which one satisfies both inequalities

27. unheard

0,5 and -4,5

28. unheard

@Peter14

29. amistre64

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

30. amistre64

(-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?

31. unheard

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

32. amistre64

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

33. unheard

It's -5, -2, right?

34. amistre64

(-5, -2) -2 <= 0 true -2 >= 1 false not that one

35. amistre64

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

36. unheard

So, it's -5, something right?

37. amistre64

dunno, lets try another one (5, -2) -2 <= 5 - 5 -2 <= 0 true -2 >= -5 - 4 -2 >= -9 true that fits nicely

38. unheard

Awesome. Thanks :)