Question

Which ordered pair is a solution for this system of inequalities?
2x + 3y > 1 and y < 5/4 x - 1

A.(3, 9)
B.(-4, 2)
C.(8, -1)
D.(-2, -5)

Answer 1

If A was the answer (that's an if), then (3,9) should satisfy both inequalities

Answer 2

2x + 3y > 1

2*3 + 3*9 > 1

6+27 > 1

33 > 1

So the first one works, let's try the second

Answer 3

y < 5/4 x - 1

9 < (5/4)(3) - 1

9 < 15/4 - 1

9 < 3.75 - 1

9 < 2.75

but the second one does NOT work

Answer 4

So choice A is NOT the answer

Answer 5

Do the same with the other answer choices to see if the ordered pair works with BOTH inequalities

Answer 6

c

Answer 7

okay thank you, Jim.

Answer 8

you're welcome

Answer 9

let me know which answer you get

Answer 10

i got C for my answer.

Answer 11

Let's see if that's true or not

2x + 3y > 1

2(8) + 3(-1) > 1

16 - 3 > 1

13 > 1 ... True

---------------

y < 5/4 x - 1

-1 < (5/4)(8) - 1

-1 < 40/4 - 1

-1 < 10 - 1

-1 < 9 ... also True

Since both inequalities are true, (8,-1) is indeed a solution

Answer 12

so you are correct

Answer 13

thanks again

Answer 14

sure thing

Answer 15

what about, Solve the system of equations using any method. Find the value of y.
6x + 3y = 12 and 5x + 3y = 0

Answer 16

options:
-20
-12
20
12

Answer 17

notice we have 3y in both equations

Answer 18

so if you subtract equation 2 from equation 1, what do you get?

Answer 19

6x + 3y = 12
5x + 3y = 0
-----------
??? ??? ???

Answer 20

1x=12 ?

Answer 21

good, so x = 12

Answer 22

now use this to find y


6x + 3y = 12

6(12) + 3y = 12

72 + 3y = 12


I'll let you finish

Answer 23

y=-20

Answer 24

good, you got it

Answer 25

can i message you with more problems? i am taking my final exam and your help is really good

Answer 26

sure, go ahead