Question

Select the ordered pair from the choices below that is a solution to the following system of equations:
5y = x − 7
4x − y = -10

a. (-8, 3)
b. (1/5, 8)
c. (-3, -2)
d. (-1, -1)

Answer 1

Hello :)
u want answer or learn Modom ?

Answer 2

I can try and learn it, I'm really bad at algebra :(

Answer 3

But we can answer together :)
OK ?

Answer 4

Yes :D

Answer 5

To find x or y we should be find one of them first :)
Which one do u like ?
X or y ?

Answer 6

x

Answer 7

To find x we should killing Y s !!!
Its so fun :)!
To killing them y1+y2=0
OK ?!

Answer 8

ok

Answer 9

Now we have
-y and 5y .
So cant kill them :)
OK ?

Answer 10

ok lol

Answer 11

To killing them we should have -5y +5y
Means -y*5
OK ?!

Answer 12

ok :D

Answer 13

Did u understand ?:)

Answer 14

Kind off :( With the info i kind of learned im gonna say its b :/

Answer 15

Maenns yes or No ?
It was important :)

Answer 16

no

Answer 17

so we killed the y's and we have -y*5 rite

Answer 18

Ok :)
No problem :)
We can start again :)

Answer 19

@AsleyXoXo :So smart !

Answer 20

:D thank u

Answer 21

So for each of the coordinates given, (aka a,b,c,etc) They are all in the form of (x,y). So just substitute in whatever x is given into the formula
so 5y= x-7, let's try plugging in a.(-8, 3)
so 5(3) b/c the form is (x,y) = (-8) -7
= 15 = -15
this is not equal. so It isn't a solution for 5y = x - 7

Answer 22

Now look :
First we wanted X s so we should kill the y because we cant caculate them together :)
OK?

Answer 23

You can do the same with b. and plug that into the same equation and if it doesn't work, go onto c. and d. for the solutions.

Answer 24

@ittskathherine :I said to u dont give the annnnnnnssssssswer .....

Answer 25

ok

Answer 26

@E.ali I was just showing her a simpler way of solving for it, I used a. as an example, so I didn't give away the whole answer.

Answer 27

you guys are smart :/

Answer 28

@AsleyXoXo:Did u understand ittskathherine s way ?????!!!!!!

Answer 29

I can tell you an even simpler way. You know when you graph, you get the coordinates (x,y)? That's what's here. Whatever number that's in the first blank between the parenthesis, is the x. (_,y). And whatever number that's in the second blank between the parentheses is the y. (x, _) I put blank spaces in there so that you can plug in whatever number they give you.

Answer 30

i need to go back to pre algebra, they put me in algebra, i never toke pre algebra

Answer 31

So for b. it lists, (1/5, 8) so one-fifths, eight.
Which means, 1/5 is x
and 8 is y. because of (x,y)

Answer 32

ok

Answer 33

and c. is (-3,-2)
which means, -3 is x
and -2 is y. Get it? Can you tell me which number in d. is x and which is y? So i can see if you understand.

Answer 34

1/5=x , 8=y rite/

Answer 35

yes

Answer 36

so what do we do with those numbers

Answer 37

In this case, for d. (the numbers are the exact same, so it doesn't matter which is x and which is y) But you should get the idea. The left side is x, and the right side is y.
You know that formula they give you?
5y= x -7.
You plug in the numbers from a. (which we already did), b.,c.,and d.

Answer 38

So where y is, you would plug in the y number (aka 8) and where x is, you plug in the x number, (aka 1/5)

Answer 39

so then you would end up with an equation like this
5 (8) = (1/5) -7. They want you to solve the equation.
so 5 times 8 is 40, 1/5 - 7 is equal to 7/35 - 35/35
so 40= -28/35
But however, these are not equal so therefore it is not the solution. Try it with C. and D.

Answer 40

@ittskathherine , you should let @E.ali to show his work!

Answer 41

so c would be x=3, y =-2

Answer 42

@PFEH.1999 He isn't replying though and she didn't really understand his way...

Answer 43

But yes, you are right @AsleyXoXo

Answer 44

ok,show your work,she won't understand you if i interrupt you :)

Answer 45

so we plug those numbers into 5y = x − 7

Answer 46

Yes, plug it in. Since you identified y and x, you can switch those numbers where x and y are

Answer 47

-2y = -3x

Answer 48

Not exactly, because
5y = x-7
so 5(-2) = (-3) -7

Answer 49

so then you would put -2 where Y is because that's how it is in its coordinates. same with x

Answer 50

so we plug those numbers into 5y = x − 7

Answer 51

so multiply the 2 y's and x's rite

Answer 52

We don't multiply them with y and x. we replace them with x and y

Answer 53

we end up with this so 5(-2) = (-3) -7

Answer 54

YES

Answer 55

what do we do to those numbers?

Answer 56

Since 5 is multiplying y, (and we replaced y with -2, we multiply 5 with -2)
and since x is subtracting 7, (and we replaced x with -3, we subtract 7 from -3.)

Answer 57

-10, -10

Answer 58

So yup! since they're equal, C., is a solution to 5y = x-7

Answer 59

Makes sense now?

Answer 60

Yes it does :D , i learned something new thanks a lot every one for helping

Answer 61

no problem

Answer 62

i got 70% on my quiz, thank u all once again <3