## yayasims21 2 years ago need help solve this equation using the elimination method 6x – 4y = 54 –9x + 2y = –69

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1. ajprincess

Multiply the second equation by 2 nd can u plz tell me vat u get?

2. yayasims21

-18+4y=-138

3. ajprincess

yup good:) nw add this one with the first equation. terms with variable y will be elimnated. then solve for x. can u do it @yayasims21

4. yayasims21

i cannt can u do it

5. ajprincess

plz give it a try. if u face any difficulty when doing it plz ask. I will help u:)

6. yayasims21

ok so im suppose to add -18+4y=-138 to 6x-4y=54

7. ajprincess

ya:)

8. yayasims21

i cant do it my calculator wont let me

9. ajprincess

-18x+4y+6x-4y=-138+54 (-18x+6x)+(4y-4y)=-138+54 See if u can do it nw:)

10. ajprincess

Add the ones inside the parentheses

11. yayasims21

i cant do it i really suck at math

12. ajprincess

what is -18x+6x?

13. yayasims21

-12

14. ajprincess

-12x. what is 4y-4y?

15. yayasims21

0

16. ajprincess

yup right:) what is -138+54

17. yayasims21

-84

18. ajprincess

yup good. nw combine these results.

19. yayasims21

20. ajprincess

ya.

21. yayasims21

i get -96

22. TheViper

@ajprincess happy new year & to @yayasims21 too :)

23. yayasims21

o thanks happy new year to u 2

24. TheViper

:)

25. ajprincess

no. remember u can add -12x with -84. nd -84 is in the right side of the equal aign. -18x+6x+4y-4y=-138+54 -12x+0=-84 -12x=-84 Divide by -12 both sides to find x. Thanx @TheViper and I wish u the same:)

26. TheViper

:)

27. yayasims21

-12 divided by -12 is 1 and -84 is 7

28. ajprincess

remember u r dividing -12x by -12 nt -12. this leaves u with x and u r right abt getting 7:)

29. ajprincess

So ur x becomes 7. To find y plug in this value in either 6x – 4y = 54 or –9x + 2y = –69 and solve

30. yayasims21

ok wat do u mean how am i suppose to do tht

31. ajprincess

x=7. Plug this in 6x-4y=54 6(7)-4y=54 42-4y=54 1.Subtract 42 both sides. 2.Divide by -4 both sides to find y.

32. yayasims21

i cant do this im so confused

33. ajprincess

42-4y=54 1.Subtract 42 both sides. 2.Divide by -4 both sides to find y.

34. ajprincess

35. yayasims21

i am but so im suppose to subtract 42from -9

36. ajprincess

no. let me do one step and show. 42-4y=54 Subtract 42 both sides 42-42-4y=54-42 0-4y=12 -4y=12 Nw divide by -4 both sides to find y

37. yayasims21

-3x

38. ajprincess

-4y=12 Divide by -4 both sides (-4y)/-4=12/-4 y=-3

39. yayasims21

ok i got it is there anymore we have to do

40. ajprincess

nope. evrythng is done:)

41. yayasims21

ok well can u show this all at once so i can write it down

42. yayasims21

can you @ajprincess

43. ajprincess

Extremely sorrry @yayasims21. busy right nw.

44. yayasims21

o alright illtry to put it together

45. ajprincess

hav u finished @yayasims21?

46. ajprincess

\(6x-4y=54-(1)\) \(-9x+2y=-69-(2)\) (2)*2=>\(-18x+4y=-138-(3)\) (3)+(1)=>\(-18x+4y+6x-4y=-138+54\) \(-12x=-84\) \(-12x/-12=-84/-12\) \(x=7\) Substituting this in (1)=> \(6(7)-4y=54\) \(42-4y=54\) \(-4y=54-42\) \(-4y=12\) \(-4y/-4=12/-4\) \(y=-3\)