Problem 36 - Algebra 2

Question

Write each equation in standard form. Identify A, B, and C. \(\frac{1}{3} x-\frac{1}{3} y=-2\)

Step-by-Step Solution

Answer

The equation in standard form is \( x - y = -6 \) with \( A=1 \), \( B=-1 \), \( C=-6 \).

Step 1: Eliminate Fractions

To eliminate the fractions in the equation \( \frac{1}{3} x - \frac{1}{3} y = -2 \), multiply every term in the equation by 3. This results in \( 1x - 1y = -6 \).

Step 2: Write the Equation in Standard Form

Ensure that the equation is in the form \( Ax + By = C \). The equation we have, \( 1x - 1y = -6 \), is already in this format. Here, \( A = 1 \), \( B = -1 \), and \( C = -6 \).

Key Concepts

Linear Equations

Linear equations are fundamental in mathematics and appear frequently in various forms and applications. These are equations where each term is either a constant or the product of a constant and a single variable. The general form of a linear equation in two variables is given by \( Ax + By = C \), where \( A \), \( B \), and \( C \) are constants, and \( x \) and \( y \) are variables.

In linear equations:

• There are no exponents, square roots, or other non-linear operations on the variables.
• The graph of a linear equation in two variables is a straight line.
• The solution to a linear equation is the set of values for \( x \) and \( y \) that makes the equation true.

Understanding linear equations is crucial because they form the basis for more complex functions and systems. Recognizing the structure helps in quickly transforming any given linear expression into its standard or desired form.

Eliminating Fractions

Eliminating fractions from an equation simplifies the process of solving it. Fractions can be cumbersome, especially when the goal is to identify the coefficients easily. To eliminate fractions in an equation, you multiply every term in the equation by the least common multiple (LCM) of all the denominators. This transforms each fractional term into an integer.

For example, consider the equation \( \frac{1}{3}x - \frac{1}{3}y = -2 \). Here, the denominator is 3 for both terms. By multiplying every term by 3, we transform the equation:

• \( 3 \times \frac{1}{3}x = 1x \)
• \( 3 \times \frac{1}{3}y = 1y \)
• \( 3 \times -2 = -6 \)

After multiplying, the equation becomes \( 1x - 1y = -6 \). This process ensures no fractions remain, making it easier to handle and set the equation in standard form.

Coefficients in Equations

Coefficients are the numerical factors that multiply the variables in an equation. In a standard linear equation like \( Ax + By = C \), \( A \) and \( B \) are known as the coefficients. They play a critical role in defining the line's slope and position on a graph.

Here's why coefficients matter:

• They determine the slope of the line \/ relationship between variables. Specifically, the slope \( m \) is given by \(-\frac{A}{B}\) when the equation is in the form \( Ax + By = C \).
• Alterations in their values will change the steepness and direction of the line represented by the equation.
• In the example equation \( 1x - 1y = -6 \), the coefficients \( A = 1 \) and \( B = -1 \) tell us that the slope is \( 1 \). This means that for a unit increase in \( x \), \( y \) increases by 1 unit if rearranged.

Identifying coefficients correctly is crucial for graphing, solving, and understanding linear relationships effectively.