Question

Can someone help me with this? I don't understand this or how to do it. I have an exam after this lesson that is due by midnight! Will medal and fan for quick accurate responses!

Answer 1

what is your question??

Answer 2

What's the question?

Answer 3

1. Is elimination

Answer 4

oh i am sorry i did not relise what this was :( im only 6th grade

Answer 5

2. Is A

Answer 6

(2,1)

Answer 7

but how do you figure it out? I have to take an exam in a few min and this will be on it

Answer 8

you see a \(-7x\) and a \(+7x\) so when you add them you will get no x term
that is why elimination is easiest

Answer 9

but how do you figure out the second?

Answer 10

you can add equations together and get a new one

here it will reduce to 1 variable, from what satellite said

Answer 11

that doesnt change anything for the solutions

Answer 12

i still don't understand. Can someone walk me through it?

Answer 13

you can solve it any way you want to, it is set up to have you prpbably do the elimination way.

when you add the two equations, one variable will go to zero, you now have 1 equation and 1 variable. you can solve that for the variable. then use that to get the other

Answer 14

Please note: Just giving away what you think is the answer is NOT allowed and is not helpful anyway.

Answer 15

need to at least try out a few before learning during the test.

Answer 16

a*x + b*y = c
d*x + e*y = f
---------------adding

(a+d)*x + (b + e)*y = c + f

the point to have a+d or b+e be a zero, and removes that variable

Answer 17

The two given equations are:

7x + 5y = 19
-7x - 2y =-16
--------------


Emma: Please add these two equations together right now.
Think: What is 7x-7x?
What is 5y-2y?
What is 19-16?

Answer 18

Note, Emma, that DanJS is correct when he writes, "when you add the two equations, one variable will go to zero, you now have 1 equation and 1 variable. you can solve that for the variable. then use that to get the other"

Answer 19

Can anyone just please help walk me through it? Bc I get that you are trying to help but I don't understand what you mean.

Answer 20

I'm certain that you can combine 7 and -7. What does that give you?
combining 7x and -7x is scarcely any harder.

Emma:

7
-7
------
?

Answer 21

the lines are in a form of some number of x + some number of y = a number
A*x+B*y = C

A,B,C are just constants, numbers

Answer 22

if you add two of those forms of equations together, you can combine the like terms
total x + total y = total constant number

Answer 23

Emma:
Examples: 2-2=0
139-139=0
-238 + 238 = 0
7 - 7 = ??

Answer 24

0

Answer 25

like i showed a bit back, here you see the total x's you get are a 7x and a -7x, totals to nothing

Answer 26

Emma: see what Dan has just typed in. 7x - 7x = ???

Answer 27

7x-7x=0

Answer 28

OK. that's right!

So all you have left is:

5y = 19
-2y=-16
-----------

Combine the expressions in the left column. Your answer?

Answer 29

5y-2y=3y Do i Need to combine the 16 and -19 too?

Answer 30

@mathmale

Answer 31

@ganeshie8 @nincompoop @Hero @TheSmartOne

Answer 32

Please answer

Answer 33

Yes, your goal is to isolate \(y\)

Answer 34

5y = 19
-2y=-16
-----------
3y = 3

Answer 35

Now, Emma, divide both sides by 3. What final equation do you get?

Answer 36

\(3y = 3\)

do you know how to isolate \(y\) in above equation ?

Answer 37

Don't you divide each side by the 3?

Answer 38

Do it and see...

Answer 39

y=1

Answer 40

right?

Answer 41

Perfect!
you may look at options now

Answer 42

@ganeshie8

Answer 43

How do i get the answer 2,1 out of y=1?

Answer 44

I'll let you answer that. You should write (2,1) and not just 2,1.

What does (2,1) represent? Think.

Answer 45

Separately, what does that '1' represent?
Note that y ou solved those two equations for y and you got the result y=1.

Answer 46

does x=2 and y=1? That is the only explanation i can think of

Answer 47

Yes, that is correct, altho I'd type, "y=1 when x=2" Very good.

Now, we need to solve for x.

Go back to the original 2 equations. Pick one of them. Type the whole equation in here.