Linear Algebra - Find an equatio relating a,b,c

In summary, the conversation discusses finding a consistent linear system and determining the relationship between variables a, b, and c in order to have a solution. The bottom row of the augmented matrix represents 0x + 0y + 0z = b - a - c, which can only be true if b - c - a = 0. This means that there are two free variables and the set of points in R3 for which the system is consistent is a plane in space.
  • #1
jinksys
123
0

Homework Statement



http://i.imgur.com/FuMGN

Homework Equations


The Attempt at a Solution



I know that for a linear system to be consistent it must have one or more answers.

After some row operations I get this matrix: http://i.imgur.com/KTEkF

I know that if I have a row of zeros that I have a trivial solution, so do I need to equate b-a-c to zero?

B - A - C = 0?
 
Last edited by a moderator:
Physics news on Phys.org
  • #2
Think about what the augmented matrix represents: Ax = c, where A is your 3 x 3 matrix, x is the vector <x, y, z>, and c is the vector of constants, <a, b, c>.

The bottom row means 0x + 0y + 0z = b - a - c. Regardless of the values of x, y, and z, what is the only value that the right side could have to make an equation that had a solution?
 
  • #3
Mark44 said:
Think about what the augmented matrix represents: Ax = c, where A is your 3 x 3 matrix, x is the vector <x, y, z>, and c is the vector of constants, <a, b, c>.

The bottom row means 0x + 0y + 0z = b - a - c. Regardless of the values of x, y, and z, what is the only value that the right side could have to make an equation that had a solution?

Zero. So the relationship between a,b, and c is b-c-a=0, correct?
 
  • #4
Right. So the system of equations is consistent provided that b - c - a = 0. If two variables are specified, the third can be found. That means that there are two free variables, and therefore, the set of points in R3 for which the system of equations is consistent is a plane in space.
 
  • #5
Mark44 said:
Right. So the system of equations is consistent provided that b - c - a = 0. If two variables are specified, the third can be found. That means that there are two free variables, and therefore, the set of points in R3 for which the system of equations is consistent is a plane in space.

Thank you for the help.
 

Related to Linear Algebra - Find an equatio relating a,b,c

1. What is a linear equation in terms of a, b, and c?

A linear equation in terms of a, b, and c is an equation in the form of ax + by + c = 0, where a, b, and c are constants and x and y are variables. It represents a straight line on a graph and can be used to solve for the values of x and y.

2. How do I solve for the values of a, b, and c in a linear equation?

To solve for the values of a, b, and c in a linear equation, you can use a system of equations. Set up two equations with two unknowns using the given values and then solve for the unknowns using algebraic methods such as substitution or elimination.

3. What is the slope-intercept form of a linear equation?

The slope-intercept form of a linear equation is y = mx + b, where m is the slope of the line and b is the y-intercept (the point where the line crosses the y-axis). This form is useful for graphing and can be derived from the standard form ax + by + c = 0.

4. Can a linear equation have more than two variables?

Yes, a linear equation can have more than two variables. In fact, the general form of a linear equation is ax1 + bx2 + ... + zxn + c = 0, where n is the number of variables. However, the most common forms of linear equations have only two variables.

5. How is linear algebra used in real life?

Linear algebra is used in many real-life applications, including computer graphics, data analysis, engineering, and economics. It is also used in physics and chemistry to model and solve systems of equations. Additionally, linear algebra is the foundation for more advanced mathematical concepts such as calculus and differential equations.

Similar threads

  • Calculus and Beyond Homework Help
Replies
1
Views
355
  • Calculus and Beyond Homework Help
Replies
4
Views
1K
  • Calculus and Beyond Homework Help
Replies
25
Views
2K
  • Calculus and Beyond Homework Help
Replies
6
Views
995
  • Calculus and Beyond Homework Help
Replies
2
Views
1K
  • Calculus and Beyond Homework Help
Replies
5
Views
2K
  • Calculus and Beyond Homework Help
Replies
18
Views
1K
  • Calculus and Beyond Homework Help
Replies
15
Views
783
  • Calculus and Beyond Homework Help
Replies
2
Views
2K
  • Calculus and Beyond Homework Help
Replies
5
Views
1K
Back
Top