Comments on: How to Solve the system of equations using the Addition method? http://www.mathstudenthelp.info/addition/how-to-solve-the-system-of-equations-using-the-addition-method Let us help you add it up! Mon, 21 May 2012 09:41:31 +0000 http://wordpress.org/?v=2.7 hourly 1 By: Filby http://www.mathstudenthelp.info/addition/how-to-solve-the-system-of-equations-using-the-addition-method/comment-page-1#comment-7023 Filby Wed, 06 Jan 2010 11:28:59 +0000 http://www.mathstudenthelp.info/addition/how-to-solve-the-system-of-equations-using-the-addition-method#comment-7023 Remember that you can add as well as subtract equations ad you can multiply equations by anything as long as you do the same to both sides 2a + 3b = -1 multiply b 3 6a + 9b = -3 3a + 5b = -2 multiply by 2 6a + 10b = -4 You now have 6a in both Subract the second from the first (6 - 6)a + (10- 9)b = (-4 - (-3)) b = -1 so a = +1<br><b>References : </b><br> Remember that you can add as well as subtract equations ad you can multiply equations by anything as long as you do the same to both sides

2a + 3b = -1
multiply b 3
6a + 9b = -3

3a + 5b = -2
multiply by 2
6a + 10b = -4

You now have 6a in both
Subract the second from the first
(6 - 6)a + (10- 9)b = (-4 - (-3))
b = -1
so a = +1
References :

]]> By: HPV http://www.mathstudenthelp.info/addition/how-to-solve-the-system-of-equations-using-the-addition-method/comment-page-1#comment-7022 HPV Wed, 06 Jan 2010 10:55:59 +0000 http://www.mathstudenthelp.info/addition/how-to-solve-the-system-of-equations-using-the-addition-method#comment-7022 You can MAKE a variable cancel by multiplying each equation by the coefficient of the variable you want to eliminate. For example: 2a + 3b = -1 3a + 5b = -2 Say we wnat to eliminate the "a" term. The first equation has "2a" and the second one has "3a." Multiply the first equation by 3 and the second equation by 2. 6a + 9b = -3 6a + 10b = -4 Now subtract the second equation from the first one. . .6a + 9b = -3 - .6a + 10b = -4 ============== -b = 1 . . . . .so b = -1; to find a, put b = -1 into either of the two original equations. Using eq. 1, 2a + 3(-1) = -1 2a - 3 = -1 2a = 2 a = 1<br><b>References : </b><br> You can MAKE a variable cancel by multiplying each equation by the coefficient of the variable you want to eliminate. For example:

2a + 3b = -1
3a + 5b = -2

Say we wnat to eliminate the "a" term. The first equation has "2a" and the second one has "3a." Multiply the first equation by 3 and the second equation by 2.

6a + 9b = -3
6a + 10b = -4

Now subtract the second equation from the first one.

. .6a + 9b = -3
- .6a + 10b = -4
==============
-b = 1 . . . . .so b = -1; to find a, put b = -1 into either of the two original equations.

Using eq. 1, 2a + 3(-1) = -1
2a - 3 = -1
2a = 2
a = 1
References :

]]> By: Ghr http://www.mathstudenthelp.info/addition/how-to-solve-the-system-of-equations-using-the-addition-method/comment-page-1#comment-7021 Ghr Wed, 06 Jan 2010 10:40:59 +0000 http://www.mathstudenthelp.info/addition/how-to-solve-the-system-of-equations-using-the-addition-method#comment-7021 equation number 1 time 3 and the second equation time -2 we get 6a+9b=-3 -6a-10b=4 the we add them together -b=1 b=-1 we replace in 1 :2a-3=-1 give us a=1<br><b>References : </b><br> equation number 1 time 3 and the second equation time -2
we get
6a+9b=-3
-6a-10b=4

the we add them together
-b=1
b=-1
we replace in 1 :2a-3=-1 give us a=1
References :

]]> By: BF http://www.mathstudenthelp.info/addition/how-to-solve-the-system-of-equations-using-the-addition-method/comment-page-1#comment-7020 BF Wed, 06 Jan 2010 10:22:59 +0000 http://www.mathstudenthelp.info/addition/how-to-solve-the-system-of-equations-using-the-addition-method#comment-7020 multiply the first equation by -3/2 (both sides) to give you -3a -9/2b=3/2 Add the two equations together. The a's will cancel out and you will be left with only b. Solve for b. Once you have solved for b, plug that value into either of the equations to get a.<br><b>References : </b><br> multiply the first equation by -3/2 (both sides) to give you -3a -9/2b=3/2
Add the two equations together. The a’s will cancel out and you will be left with only b. Solve for b. Once you have solved for b, plug that value into either of the equations to get a.
References :

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