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#1076 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-27 09:41:09
4x + 3y = -15 + 2 + -1x
Combine like terms: -15 + 2 = -13
4x + 3y = -13 + -1x
4x + 3y = -13 + -1x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add 'x' to each side of the equation.
4x + x + 3y = -13 + -1x + x
Combine like terms: 4x + x = 5x
5x + 3y = -13 + -1x + x
Combine like terms: -1x + x = 0
5x + 3y = -13 + 0
5x + 3y = -13
Add '-3y' to each side of the equation.
5x + 3y + -3y = -13 + -3y
Combine like terms: 3y + -3y = 0
5x + 0 = -13 + -3y
5x = -13 + -3y
Divide each side by '5'.
x = -2.6 + -0.6y
#1077 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-27 06:44:10
bobbym thanx
ooh and i was wondering is this first step correct 4x+3y-x+2=-15
#1078 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-27 06:42:54
hey anonimnystefy yeah it is really much easier to do it in the substitution method but am asked to do the following for an online algebra course she wants me to show in the elimination method and am finding it really hard 
#1079 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-27 05:35:24
am ganna need help doing these in the elimination method
12. 4x + 3y = -15
y = x + 2
13. x + 2y = -4
4y = 3x + 12
14. y = 2x
x + y = 3
15. x = 3 - 3y
x + 3y = -6
16. y = -2x + 1
y = x - 5
17. y = (1/2)x - 3
y = (3/2)x 1
18. x + y = 2
4y = -4x + 8
#1080 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-27 03:31:38
thanx guys
#1081 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-27 03:30:25
for number 11 i tried to do it using the elimination method
x+y=0
3x+y=-4
4x+y=-4
4x=-4
x=-1
3x-1+y=-4
3x-1
-3+y=-4
-3+3+y=-4+3
-3-3=0
0+y=-4+3
y=-4+3
y=-1
#1082 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-27 01:55:38
thank alot anonimnystefy
#1083 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-27 01:54:36
for number 11 i tried to do it using the elimination method
x+y=0
3x+y=-4
4x+y=-4
4x=-4
x=-1
3x-1+y=-4
3x-1
-3+y=-4
-3+3+y=-4+3
-3-3=0
0+y=-4+3
y=-4+3
y=-1
#1084 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-27 01:47:08
thanx bobbym and anonimnystefy i will thanx 
#1085 Re: Introductions » heyy » 2011-06-27 01:06:39
hey ) thanx
#1086 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-27 01:03:47
i was wondering if i did number 4 correct
x + 2y = -4
4y = 3x + 12
x+2y=-4
x+2y+-2y=-4+-2y
2y+-2y=0
x+0=-4+-2y
x=-4+-2y
4y=3(-4+-2y)+12
4y=(-12+-6y)+12
-12+12=0
4y=0+-6y
4y=-6y
4y+6y=-6y+6y
4y+6y=10y
10y=-6y+6y
10y=0
y=0
#1087 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-26 10:09:18
really thats it thats the elimination method
#1088 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-26 09:55:12
so x is ganna be 3
#1089 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-26 09:54:06
yup am working on it this is ganna take a while am slow in math 
#1090 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-26 09:38:04
10. y = (2/3)x - 1
y = -x + 4
11. x + y = 0
3x + y = -4
12. 4x + 3y = -15
y = x + 2
13. x + 2y = -4
4y = 3x + 12
14. y = 2x
x + y = 3
15. x = 3 - 3y
x + 3y = -6
16.
y = -2x + 1
y = x - 5
17. y = (1/2)x - 3
y = (3/2)x 1
18. x + y = 2
4y = -4x + 8
these are the problems am talking about
like am i ganna end up with x in all of them ???
#1091 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-26 09:36:36
really so whats the point of doing the elimination method am ganna end up with x in the end :? am still confused
#1092 Introductions » heyy » 2011-06-26 09:33:54
- zee-f
- Replies: 9
hey guys and girls am sarah am born in michigan am 15 years old am a female
i study online since i moved from michigan to Kuwait (arab country )
i enjoy staying online alot i am having trouble studying i really like this website its helping alot in my algebra course ) and ill pretty sure enjoy having math friend here )
#1093 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-26 09:29:20
like for this one i have to do numbers 10-18 in the elimination method for number
10. y = (2/3)x - 1
y = -x + 4
so am i spouse to subtract the -x and the 2/3 ??
#1094 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-26 09:20:07
am really confused on how to do the elimination method
bobbym thanx alot for the help
#1095 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-26 02:56:24
heyyy i solved the following and i was wondering if i did them correct
#5- y=2x
x+y=3
x+2x=3
-2x -2x
x+2x=3
-2x -2x
x+2x=3x
3x=3
x=1
y=2*1
#6- x=3-3y
x+3y=-6
x= 3-3y
3-3y+3y=-6
-3y+3y=0
3+0=-6
3=-6
so it has no solution
#7- y=-2x+1
y=x-5
-2x+1=x-5
-1 -1
-2x=-6+x
-2x=-6+x
-2x+-1x=-6+x+-1x
-2x+-1x=-3x
-3x=-6+x+-1x
x+-1x=0
-3x=-6+0
-3x=-6
x=2
-2*2+1=-3
y=-3
#8-
y= (1 / 2) x-2
y= (3 / 2) x-1
1/2x-2=3/2x-1
added -1/2x to each side
-2+1/2+-3/2
-2+1/2x+-3/2x=-1+3/2x+-3/2
1/2x+-3/2x=-1x
-2+-1x=-1+3/2x+-3/2x
3/2x+-3/2x=0
-2+-1x=-1+0
-2+-1x=-1
#9-
x+y=2
4y=-4x+8
x+y=2
x+y+-1y=2+-1y
y+-1y=0
x+0=2+-1y
x=2+-1y
4y=-4(2+-1y)+8
4y=-8+4y+8
-8+8=0
4y=0+4y
4y=4y
4y+4y=4y+-4y
4y+-4y=0
0=4y+-4y
4y+-4y=0
0=0
#1096 Re: Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-21 05:41:05
thanx for the help
#1097 Help Me ! » Solving systems of equations using Substitution method and elimination » 2011-06-21 05:04:57
- zee-f
- Replies: 193
i need help solving the following
for the first one this is what i did
or at least try to do
y=(2/3)x-1
y=-x-4
-x+4=(2/3)x-1
1. y = (2/3)x - 1
y = -x + 4
2. x + y = 0
3x + y = -4
3. 4x + 3y = -15
y = x + 2
4. x + 2y = -4
4y = 3x + 12
5. y = 2x
x + y = 3
6. x = 3 - 3y
x + 3y = -6
7. y = -2x + 1
y = x - 5
8. y = (1/2)x - 3
y = (3/2)x 1
9. x + y = 2
4y = -4x + 8
Solve numbers 10 18 using the elimination method. Show your work.
10. y = (2/3)x - 1
y = -x + 4
11. x + y = 0
3x + y = -4
12. 4x + 3y = -15
y = x + 2
13. x + 2y = -4
4y = 3x + 12
14. y = 2x
x + y = 3
15. x = 3 - 3y
x + 3y = -6
16. y = -2x + 1
y = x - 5
17. y = (1/2)x - 3
y = (3/2)x 1
18. x + y = 2
4y = -4x + 8
19. Why are the substitution and elimination methods necessary when we already know how to solve systems of linear equations using the graphing method?
#1098 Re: Help Me ! » Review of Applications of Linear Equations » 2011-06-18 02:50:26
it sure dose thanx for asking
#1099 Re: Help Me ! » Review of Applications of Linear Equations » 2011-06-18 01:37:56
hey bobbym yup i am am getting better thanks to this website and the practices am doing
#1100 Re: Help Me ! » Review of Applications of Linear Equations » 2011-06-18 01:22:19
thank you