Systems of linear equations can be used to solve many, but not all, real-world problems. When you chose the problem for your journal entry, how did you know that this problem could be solved using a system of linear equations? What specific characteristics does your problem have that made it a good choice? List at least three reasons why the problem you described in your journal prompt can be solved using a system of linear equations.

Post a detailed response to the questions about your choice of a real-world problem to solve using a system of linear equations. Then respond to two classmates' posts.

Participate in the discussion to learn more about how to determine if a real-world problem can be solved using systems of linear equations.

1 answer

When selecting a real-world problem that could be addressed using a system of linear equations, I considered various factors that typically indicate the applicability of this mathematical approach. The specific problem I chose involved determining the costs of two different types of fruit—a certain number of apples and oranges—given their combined total cost and quantity.

Here are three specific characteristics of the problem that made it a good choice for solving with a system of linear equations:

  1. Multiple Variables: The problem involved two different unknowns: the cost per apple and the cost per orange. Systems of linear equations are suitable for problems where you need to determine the values of multiple variables that are interrelated.

  2. Linear Relationships: The relationships between the variables in my problem are linear. For example, if I have a certain number of apples and oranges, the total cost can be expressed as a linear equation (e.g., the total cost of apples plus the total cost of oranges equals the overall amount spent). This direct proportionality between the quantities and their costs makes the use of linear equations appropriate.

  3. Constraints Leading to Equations: The problem naturally provided two distinct constraints: the total quantity of fruit and the combined cost. Each constraint allows us to formulate a linear equation. This duality is crucial when solving systems of equations, as it provides a basis for finding the unique solution that satisfies both conditions simultaneously.

In summary, selecting a problem to solve with a system of linear equations requires identifying multiple variables that have linear relationships and clear constraints that lead to equations. This understanding plays a fundamental role in determining the appropriateness of using linear algebra to find solutions to real-world situations.