Question

Need help with elimination. I would like somebody to please help me work through the problem. I do like to write them down so please allow at least 30 seconds for me to write what you said. It would be greatly appreciated if somebody would help me LEARN. No answers until I figure it out for myself, please! Thanks! Equation below.

2x+6y=-12
5x-5y=10.

I know I have to multiply by a number for the first step but that's the problem, I don't know what number. How do I know? Answer this question first please. After that though, please help me work through it. :)) Thanks guys! Will medal/fan

Answer 1

Greatly appreciate any help, even tips! thanks all.

Answer 2

2x+6y=-12
divide each term with 2,u will get
x+3y = -6 --------I
sx-5y=10
divide each term with 5
x-y= 2--------II

Answer 3

subtract II from I

Answer 4

4y= -8
y= -8/4
y=-2

Answer 5

Oh. so we have to divide? I thought we had to multiply. Let me read the rest of your response. :)

Answer 6

it can be done by multiplication also but you have to deal with some big numbers

Answer 7

I just wrote it down and i understand now. Thank you very much. :)) Will medal and fan be okay? :)

Answer 8

Oh. Okay. Well, how about x now that we found y?

Answer 9

Plug it in maybe?

Answer 10

ok
substitute y=-2 in one of eqations u get x value
can u do that

Answer 11

Mmhm. I will start writing now. What equation do I plug it in? Or doesn't it matter?

Answer 12

Ok, I got ya! Didn't read it correctly the first time. So it is either equation.

Answer 13

right

Answer 14

0?

Answer 15

excellent

Answer 16

So, (0,-2)?

Answer 17

Thank you so much!!

Answer 18

right

Answer 19

One more thing.

Answer 20

ok,any more

Answer 21

What is the solution of the following system?
-3x-2y=-12
9x+6y=-9.

How do I know if i should substitute or eliminate? That's all I need to know for this. :)

Answer 22

in first eqation multiply with (-) both sides

Answer 23

3x+2y=12-------I

Answer 24

Okay, so what would that be? Substitution or elimination?

Answer 25

second equation divide with 3 both sides

Answer 26

3x+2y=-3-------II

Answer 27

okay, I am writing. :)

Answer 28

Got it. Then what?

Answer 29

Hm. They look almost the same.

Answer 30

in both eqations has x,y coefficients equal

Answer 31

except constant term, here RHS PART

Answer 32

What does that mean? RHS PART?

Answer 33

THEREFORE TWO EQUATIONS SHOWS parellel lines

Answer 34

right hand side=RHS

Answer 35

Does that mean many solutions? That is a choice in my book.

Answer 36

Sorry if I'm wrong.

Answer 37

NO SOLUTION

Answer 38

Oh. Okay. Why would it be no solution?

Answer 39

BECAUSE,two lines never intersect,how can u get common point mean solution

Answer 40

Ohhh. I got it now! Thank you. You are a life saver. :) Thank you for the knowledge. I love learning. That is all I need. :)

Answer 41

wait

Answer 42

hm?

Answer 43

ok

Answer 44

I will save that for future reference. :)