It depends on how complex they are
1/4 of my final year of maths degree was devoted to this so this gives some idea of how large the subject is
Anyways, subsititution is the basic method for very simple equations
what equation ar eyou trying to solve - email me if you want
2007-04-22 00:45:58
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answer #1
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answered by Sean JTR 7
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Remember any EQUATION has to be EQUAL at all times -
Whatever you do to Left Hand Side (LHS) you MUST also do to Right Hand Side (RHS)
Suppose you were asked to solve:
3b + 2c = 46
3c + b = 11
One way of approaching the question
3b + 2c = 46....................Eq 1
3c + b = 11 ....................Eq 2
Rearrange Eq 2
b = 11 - 3c ..........................Eq 3
Substitute for b in Eq 1
3(11 - 3c) + 2c = 46
Expand terms
33 - 9c + 2c = 46
Collect terms and rearrange
-7c = 46 - 33
7c = -13
c = - (13/7)
c = - 1.9
Substitute for c in Eq 2
3 (-13/7) + b = 11
Rearrange and expand
b = 11 + (39/7)
b = 16.6
OR
You could combine Eq 1 & Eq 2 by rearranging and Subtraction
Eq 1 ............. 3b + 2c = 46
Eq 2 .............. b + 3c = 11
Multiply Eq 2 by 3 (Make coefficient of b the same as it is in Eq 1)
Eq 3 ................3b + 9c = 33
Combine both Equations by subtraction to 'remove' term in 'b'
Eq 1 - Eq 3..... -7c = 13
c = - 13/7
Substitute in Eq 2
3 (-13/7) + b = 11
Rearrange
b = 11 + (39/7)
Depending on the figures you start with, if you follow the steps I have shown, you should be able to deal with ANY pair of Linear Simultaneous Equations
Live Maths ------- Love Maths ------- Breathe Maths
2007-04-24 07:07:59
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answer #2
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answered by Rod Mac 5
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nicely first u label them 2x = 3y ........ a million 2y + x = 7......2 sparkling up 2 for x, so: x = -2y + 7 next u substitute x into quantity a million: 2(-2y + 7) = 3y -4y + 14 = 3y -7y = -14 y = 2 now ultimately to sparkling up for x, substitute the fee of y into quantity one: 2x = 3(2) 2x = 6 x = 3 for this reason, the fee of x is 3 and y is two is often written as (3,2) for a graphing co-ordinate word: the guy who commented first is inaccurate. x can not be 6 and y can not be 2 because of the equation as information. if we substitute those values into the 2x = 3y, it would not equivalent one yet another, at the same time with: 2(6) = 3(2) 12 = 6 incorrect!!!!!!
2016-12-16 12:32:53
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answer #3
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answered by ? 4
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Yes.
By substitution, elimination, or any one of the methods you already know.
If you have a calculator like mine you can solve linear simultaneous equations with 2 or 3 variables.
You could also try matlab.
2007-04-22 00:45:46
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answer #4
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answered by Dr D 7
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Consider the following examples:-
Example1
3x + 4y = 18
5x + 2y = 16
3x + 4y = 18
- 10x - 4y = - 32 CAN NOW ADD
- 7 x = - 14
7x = 14
x = 2
3x + 4y = 18
6 + 4y = 18
4y = 12
y = 3
x = 2 , y = 3
Example 2
2x - 4y = 10
3x + 2y = 7
2x - 4y = 10
6x + 4y = 14-------- ADD
8x = 24
x = 3
18 + 4y = 14
4y = - 4
y = - 1
x = 3 , y = - 1
Example 3
4x - 3y = 12
- 2x + 5y = 8
4x - 3y = 12
-4x + 10y = 16----ADD
7y = 28
y = 4
4x - 12 = 12
4x = 24
x = 6
x = 6,y = 4
Hope you can follow these examples.
2007-04-22 01:12:04
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answer #5
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answered by Como 7
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For two simultaneous equations, each with y and x, convert them into the following type:
ax+by=e
cx+dy=f
and then:
x = (de-bf)/(ad-bc)
y = (af-ce)/(ad-bc)
For more equations and variables (so with z etc.) you can use row and column operations on matrices (if you are familiar with matrices) - try searching on the web, I can't find anything good though.
2007-04-22 01:03:08
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answer #6
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answered by Anonymous
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Assuming you have the same number of equations as you do variables, you can use substitution or elimination. Substitution means solving for one variable and substituting that for the second variable. Elimination means to add, subtract, mutiply, or divide the two equations to get rid of one variable, then inputting that solution in to the equation of one of the variables.
2007-04-22 01:00:57
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answer #7
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answered by christianprogrammer2 4
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use gauss jordan Method or row reduction method
2007-04-22 02:07:43
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answer #8
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answered by mkkosgei 1
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Yes, do your homework regularly and study hard. That will make them easy.
2007-04-22 03:59:05
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answer #9
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answered by Anonymous
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