Not checking for infinitely many solutions

Oct 13, 2025 by wbrum.org 69 views

Introduction

In the field of business studies, linear equations play a crucial role in modeling various business scenarios. One such equation is 3x + 5y = 12, which can be used to represent a wide range of business problems. In this article, we will explore three different approaches to solve this equation, providing readers with a comprehensive understanding of the subject.

Approach 1: Substitution Method

The substitution method is a popular approach to solving linear equations. This method involves substituting the value of one variable in terms of the other variable into the equation. To solve the equation 3x + 5y = 12 using the substitution method, we can start by isolating one of the variables.

Step 1: Isolate One Variable

Let's isolate the variable x by subtracting 5y from both sides of the equation:

3x = 12 - 5y

Step 2: Solve for x

Now, we can solve for x by dividing both sides of the equation by 3:

x = (12 - 5y) / 3

Step 3: Find the Value of y

To find the value of y, we can substitute the value of x into the equation 3x + 5y = 12. However, since we have expressed x in terms of y, we can substitute the expression for x into the equation:

3((12 - 5y) / 3) + 5y = 12

Simplifying the equation, we get:

12 - 5y + 5y = 12

This equation is true for all values of y, which means that the equation 3x + 5y = 12 has infinitely many solutions.

Approach 2: Elimination Method

The elimination method is another approach to solving linear equations. This method involves eliminating one of the variables by adding or subtracting the equations. To solve the equation 3x + 5y = 12 using the elimination method, we can start by multiplying the equation by a suitable constant.

Step 1: Multiply the Equation

Let's multiply the equation 3x + 5y = 12 by 3 to make the coefficients of x in both equations equal:

9x + 15y = 36

Step 2: Eliminate One Variable

Now, we can eliminate the variable x by subtracting the original equation from the new equation:

(9x + 15y) - (3x + 5y) = 36 - 12

Simplifying the equation, we get:

6x + 10y = 24

Step 3: Solve for y

To solve for y, we can isolate the variable y by subtracting 6x from both sides of the equation:

10y = 24 - 6x

Now, we can solve for y by dividing both sides of the equation by 10:

y = (24 - 6x) / 10

Step 4: Find the Value of x

To find the value of x, we can substitute the value of y into the equation 3x + 5y = 12. However, since we have expressed y in terms of x, we can substitute the expression for y into the equation:

3x + 5((24 - 6x) / 10) = 12

Simplifying the equation, we get:

3x + (120 - 30x) / 10 = 12

Multiplying both sides of the equation by 10, we get:

30x + 120 - 30x = 120

This equation is true for all values of x, which means that the equation 3x + 5y = 12 has infinitely many solutions.

Approach 3: Graphical Method

The graphical method is a visual approach to solving linear equations. This method involves graphing the equations on a coordinate plane and finding the point of intersection. To solve the equation 3x + 5y = 12 using the graphical method, we can start by graphing the equation on a coordinate plane.

Step 1: Graph the Equation

Let's graph the equation 3x + 5y = 12 on a coordinate plane. We can start by finding the x-intercept by setting y = 0:

3x + 5(0) = 12

Simplifying the equation, we get:

3x = 12

Now, we can solve for x by dividing both sides of the equation by 3:

x = 4

The x-intercept is (4, 0).

Step 2: Find the y-Intercept

To find the y-intercept, we can set x = 0:

3(0) + 5y = 12

Simplifying the equation, we get:

5y = 12

Now, we can solve for y by dividing both sides of the equation by 5:

y = 12 / 5

The y-intercept is (0, 12/5).

Step 3: Find the Point of Intersection

The point of intersection is the solution to the equation 3x + 5y = 12. Since the equation has infinitely many solutions, we can see that the point of intersection is a line, not a single point.

Conclusion

In this article, we have explored three different approaches to solving the linear equation 3x + 5y = 12. The substitution method, elimination method, and graphical method are all useful approaches to solving linear equations. However, the equation 3x + 5y = 12 has infinitely many solutions, which means that the point of intersection is a line, not a single point.

Q: What is the linear equation 3x + 5y = 12?

A: The linear equation 3x + 5y = 12 is a mathematical equation that represents a linear relationship between two variables, x and y. The equation is in the form of ax + by = c, where a, b, and c are constants.

Q: What are the three approaches to solving the linear equation 3x + 5y = 12?

A: The three approaches to solving the linear equation 3x + 5y = 12 are:

Substitution Method: This method involves substituting the value of one variable in terms of the other variable into the equation.
Elimination Method: This method involves eliminating one of the variables by adding or subtracting the equations.
Graphical Method: This method involves graphing the equations on a coordinate plane and finding the point of intersection.

Q: Why does the equation 3x + 5y = 12 have infinitely many solutions?

A: The equation 3x + 5y = 12 has infinitely many solutions because it is a linear equation with two variables. This means that there are an infinite number of possible combinations of x and y that satisfy the equation.

Q: How do I graph the equation 3x + 5y = 12 on a coordinate plane?

A: To graph the equation 3x + 5y = 12 on a coordinate plane, you can start by finding the x-intercept by setting y = 0. Then, find the y-intercept by setting x = 0. Finally, plot the points of intersection and draw a line through them.

Q: What is the x-intercept of the equation 3x + 5y = 12?

A: The x-intercept of the equation 3x + 5y = 12 is (4, 0). This means that when y = 0, x = 4.

Q: What is the y-intercept of the equation 3x + 5y = 12?

A: The y-intercept of the equation 3x + 5y = 12 is (0, 12/5). This means that when x = 0, y = 12/5.

Q: How do I find the point of intersection of the equation 3x + 5y = 12?

A: To find the point of intersection of the equation 3x + 5y = 12, you can use any of the three approaches mentioned earlier: substitution method, elimination method, or graphical method.

Q: What is the significance of the point of intersection in solving the linear equation 3x + 5y = 12?

A: The point of intersection is the solution to the linear equation 3x + 5y = 12. It represents the point where the two lines intersect, and it is the value of x and y that satisfies the equation.

Q: Can I use the point of intersection to solve other linear equations?

A: Yes, you can use the point of intersection to solve other linear equations. The point of intersection is a general solution to the equation, and it can be used to find the values of x and y that satisfy other linear equations.

Q: How do I apply the concepts learned in this article to real-world problems?

A: The concepts learned in this article can be applied to real-world problems in various fields, such as business, economics, and engineering. For example, you can use linear equations to model supply and demand curves, or to optimize production levels.

Q: What are some common applications of linear equations in business and economics?

A: Some common applications of linear equations in business and economics include:

Supply and Demand Curves: Linear equations can be used to model supply and demand curves, which can help businesses understand market trends and make informed decisions.
Cost-Benefit Analysis: Linear equations can be used to analyze the costs and benefits of different business decisions, such as investing in new equipment or hiring new employees.
Optimization: Linear equations can be used to optimize production levels, inventory management, and other business processes.

Q: How do I choose the best approach to solving a linear equation?

A: The best approach to solving a linear equation depends on the specific problem and the information available. You can use the substitution method, elimination method, or graphical method, depending on the complexity of the equation and the information available.

Q: What are some common mistakes to avoid when solving linear equations?

A: Some common mistakes to avoid when solving linear equations include:

Not checking for infinitely many solutions: Make sure to check if the equation has infinitely many solutions before trying to find a specific solution.
Not using the correct method: Choose the correct method for solving the equation, depending on the complexity of the equation and the information available.
Not checking for errors: Double-check your work for errors, especially when using the graphical method.