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# Simultaneous equation help!! watch

1. Hi I'm really stuck on this simultaneous equation 3x+y=-4
3x-4y=6
I'm stuck on which method to use as there is a number of methods, any help would be much appreciated
2. See how in both equations you can see 3x, therefore i think the elimination method would be the easiest. Do you know how to do this method?
3. (Original post by El Patron555)
Hi I'm really stuck on this simultaneous equation 3x+y=-4
3x-4y=6
I'm stuck on which method to use as there is a number of methods, any help would be much appreciated
What methods do you think you should use? Any methods will work, it's just which ones would be quicker. Can you see anything that you can do really easily, relating to the x terms?
4. (Original post by ecila21)
What methods do you think you should use? Any methods will work, it's just which ones would be quicker. Can you see anything that you can do really easily, relating to the x terms?
Should I times y in the first equation by 3 as in the second equation the first number is3x??
5. (Original post by number0)
See how in both equations you can see 3x, therefore i think the elimination method would be the easiest. Do you know how to do this method?
Going to attempt that method now
6. 1. If you times y in the first equation by 3, you must also times every other term (separated by + or -) in the equation by 3.

2. In this case, you don't need to do that. Subtract equation 2 from equation one and see what you get. Remember you can only add or subtract like terms. Be careful with the double negative.
7. (Original post by s.xw)
1. If you times y in the first equation by 3, you must also times every other term (separated by + or -) in the equation by 3.

2. In this case, you don't need to do that. Subtract equation 2 from equation one and see what you get. Remember you can only add or subtract like terms. Be careful with the double negative.
I've just attempted this method and the got the answers Y= -2 and X= 0.666, I don't know if this right or not
8. You forgot the minus in front of 0.666 (2/3), so y = -2, x = -2/3. But other than that you are correct!
9. (Original post by s.xw)
You forgot the minus in front of 0.666 (2/3), so y = -2, x = -2/3. But other than that you are correct!
Thank you for your help but when you wrote x = 2/3 are basically converting it into a fraction of something?
10. (Original post by El Patron555)
Thank you for your help but when you wrote x = 2/3 are basically converting it into a fraction of something?
Yes, in maths it's a good habit to leave answers in fractions where possible.
11. (Original post by El Patron555)
I've just attempted this method and the got the answers Y= -2 and X= 0.666, I don't know if this right or not
To check, you can always put the x value into the equation and see if you come out with the y value or vice versa.
12. Hi
Please check the attachment. I hope methods are clear to you. please ask me if you any steps are not clear to you
Attached Images

13. (Original post by gurungg48)
Hi
Please check the attachment. I hope methods are clear to you. please ask me if you any steps are not clear to you
Thank you I've figured it out now, much appreciated for the word you done to try and help me

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