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INCONSISTENT

Inconsistent

Definition Of Inconsistent

Inconsistent Equations: A system of equations that has no solutions. .

Inconsistent inequalities:A system of inequalities that has no solutions.

Examples of Inconsistent

Inconsistent equations: The system of equations given below is inconsistent.
4x - 5y = 7 
8x - 10y = 7
Inconsistent inequalities: The system of inequalities given below is inconsistent. 
x - y ≤ 0 
x - y ≥ 7

Video Examples:Consistent and Inconsistent Systems
 

Solved Example on Inconsistent

Determine whether the system of equations 
0.5x - 0.3y = 1.2 
1.5x - 0.9y = 2.1 
is consistent and dependent, or inconsistent.

Choices:
A. inconsistent 
B. consistent and independent 
C. consistent and dependent 
D. consistent
Correct Answer: A 

Solution:

Step 1: 0.5x - 0.3y = 1.2 [Equation 1.]
Step 2: 1.5x - 0.9y = 2.1 [Equation 2.]
Step 3:  [Rearrange equation 1 in slope-intercept form.]
Step 4:  [Simplify.]
Step 5:   [Rearrange equation 2 in slope-intercept form.]
Step 6: 
Step 7: Graph the equations.

Step 8: The two lines are parallel.
Step 9: So, the linear system has no solution
Step 10:Therefore, the system is inconsistent

Quick Summary

  • Inconsistent equations represent parallel lines when graphed.
  • Inconsistent inequalities represent regions that do not overlap when graphed.
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🍎 Teacher Insights

Emphasize the graphical representation of inconsistent systems to provide a visual understanding. Use real-world examples where conflicting constraints lead to no feasible solution.

🎓 Prerequisites

  • Linear Equations
  • Graphing Linear Equations
  • Solving Equations
  • Inequalities

Check Your Knowledge

Q1: Which of the following systems is inconsistent?

Frequently Asked Questions

Q: How can you tell if a system is inconsistent?
A: When solving, you arrive at a contradiction (e.g., 0 = 1). Graphically, the lines are parallel (for equations) or the regions don't overlap (for inequalities).

Q: Does an inconsistent system have any solutions?
A: No, an inconsistent system by definition has no solution.

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