Solving Simultaneous Equations: Step-by-Step Guide and Explanation

In summary, the conversation is about trying to solve a system of equations with 4 variables and only 3 equations. The person suggests using substitution to find a, b, and c in terms of z and a constant. Another person recommends canceling one variable in two equations and using the remaining equations to solve for the other two variables. Eventually, the person is able to figure it out and thanks the others for their help.
  • #1
Stripe
32
0

Homework Statement


Find a,b,c,z
2a+b+2c=z
a+2b+c=4
a+b+2c=3

2. The attempt at a solution
Ok so I've tried multiplying all lines by 2 so you may possibly cancel out 2a, but not sure where to go after i multiplied everything.

Then i tried to just cancel one equation and then another one e.g

4a+5b+4c=10
4a+4b+8c=12

B-4c=-2

But not sure.

I would really like an explanation on how to actually do it rather than the answer.
 
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  • #2
the question has given 4 variables and only 3 equations so you can not find a,b,c,z what you may be able to do is find a,b,c in terms of z and a constant.

to do this continue wih the subsitition of one equation into another treating z as a constant

not sure how you got 4a+5b+4c=10, 4a+4b+8c=12

but try subsituting
a+2b+c=4
a+b+2c=3 canceling the 'a'
and do the same with
2a+b+2c=z
a+2b+c=4
then you will have 2 equations and two unkowns, I'm sure you can see where to go with that
 
  • #3
Ok thanks for the help I've figured it out. i appreciate the help :D
 

1. What are simultaneous equations?

Simultaneous equations are a set of two or more equations with multiple variables that must be solved simultaneously to find the values of the variables that satisfy all equations.

2. What is the purpose of solving simultaneous equations?

The purpose of solving simultaneous equations is to find the values of the variables that satisfy all equations. This is useful in many real-world applications, such as analyzing systems of linear equations in physics and engineering, or finding the intersection points of two graphs in mathematics.

3. What are the different methods for solving simultaneous equations?

There are several methods for solving simultaneous equations, including substitution, elimination, and graphing. Each method has its own advantages and may be more appropriate for different types of equations.

4. How do I know if a system of equations has a unique solution?

A system of equations has a unique solution if the number of equations is equal to the number of variables, and the equations are independent (i.e. they cannot be simplified to the same equation). This means there is only one set of values for the variables that satisfies all equations.

5. Can simultaneous equations have more than one solution?

Yes, depending on the number of equations and variables, a system of simultaneous equations can have one, zero, or infinitely many solutions. When there are more variables than equations, there may be multiple solutions that satisfy the equations, making the system underdetermined.

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