Question

Solve this system of equations

5x+4y=-14

3x+6y=6

Answer 1

Do you ned to use any specific method?

Answer 2

Okay for this equation we can either use substitution or elimination method. I think elimination is easier though.

Answer 3

@e.mccormick plx

Answer 4

Well, for this one, substitution might be easier... solving for x in the second one. \(\ddot \smile\) But both work really well.

Answer 5

Oh yes that's correct, my mistake. What he said^^^

Answer 6

But yes, is there a specific method they want you to use? @Keridavis

Answer 7

I agree....divide each term of the 2nd equation by 3. Then find what you would sub in for x.

Answer 8

Keri, Keri, blueberry, where have your replies gone? So many here to help you, but from you not a song.

Answer 9

^

Answer 10

? I need something simple and easy to work the problem

Answer 11

OK. Then what do you get if you solve the second equation for x?

Answer 12

Thats the problem, i have no idea how.....

Answer 13

2a + 4b = 8
Solve for a means use math to get a alone.

2a + 4b - 4b = 8 - 4b
2a = 8 - 4b
2a/2 = (8 - 4b)/2
a = 4 - 2b

You need to do the same sort of thing.

Answer 14

Once you have what x is in terms of y, or sole for x, you can use that answer to replace the x in the first equation. That will lead to knowing what y is. Then you can use y to find x.

That process is called substitution. In this case, it is easier.

Answer 15

oh. I kinda get it.

Answer 16

So, if you solve the second equation for x, what do you get?

Answer 17

Gimme a minute xD

Answer 18

One, one thousand
Two, one thousand
Three, one thousand
Four, one thousand

Gonna take me more than a minute to type 60 seconds. =P

Answer 19

xD Sorry, And I got x= 3-3y *hopes I'm right*

Answer 20

Yes. So, that is a value of x. Not a number, but still 100% valid.

So replace x in the first equation with (3-3y) and what do you get?

Answer 21

Wait, So it will be,..
" 5(3-3y)+4y = -14???

Answer 22

Exactly! Once you solve that, you will know what y is.

Answer 23

OMG! Thank you so much! No one could explain this to me at alll!

Answer 24

And once you know exactly what y is, you put that into either equation and find x.

Answer 25

An easy way to check the answer is to try y in both and make sure you get the same x. Another is to graph both lines and they should meet at the (x,y) point that solves this.

Answer 26

oh god.. I got a decimal...

Answer 27

Hmmm.... lets see.

5(3-3y)+4y = -14
15-15y+4y = -14
15-11y = -14
-11y = -14-15
-11y = -29

Well, you can leave it as a fraction. y=29/11

Answer 28

Hmmm... but when I graph it... odd. Let me see if we made a mistake somwhwere.

Answer 29

3x+6y=6
3x=6-6y
x=2-2y

Oops. Did not catch that earlier.

Answer 30

o.O? Oh.. I'm lost..

Answer 31

Try it again with (2-2y) rather than (3-3y). Just a small mistake.

Answer 32

Wait.. Where did I make that mistake??

Answer 33

it is not x = 3 - 3y

Here is the full math of it. Check yours:

3x+6y=6
3x+6y-6y =6-6y
3x=6-6y
3x/3=(6-6y)/3
x=6/3-6y/3
x=2-2y

Answer 34

It is probably in this step:
x=6/3-6y/3

You went to 3 instead of 2. A minor logical error. We all make them at times.

Answer 35

Oh, I see now. thnk you.