A linear equation is an equation where the highest power of the variable(s) is 1. In other words, the equation represents a straight line when plotted on a graph. The solutions of a linear equation are the values of the variables that satisfy the equation, meaning when substituted into the equation, both sides of the equation are equal.
Example of a Linear Equation:
2x + 3 = 7
To find the solution of this equation, we solve for xx:
-
Subtract 3 from both sides:
2x=7−3 2x=4
-
Divide both sides by 2:
x=4/2 x =
So, the solution to 2x + 3 = 7 is x = 2. This means that when x = 2, the equation holds true.
Key Concepts About Solutions of Linear Equations:
-
Single Solution (Unique Solution):
For equations with one variable, the solution is typically a single value of the variable. For example, 3x – 5 = 10 has the solution x = 5. -
Infinite Solutions:
In some cases, a linear equation can represent an identity (e.g., 2x + 4 = 2x + 4). These equations have infinitely many solutions because both sides are always equal, regardless of the value of xx. -
No Solution:
If the equation simplifies to a contradiction (e.g., 3x + 2 = 3x + 5), it has no solution because there is no value of xx that can make both sides equal. -
Graphical Interpretation:
-
In the case of a single-variable linear equation (e.g., 2x + 3 = 7), the solution is the point where the graph of the equation intersects the x-axis.
-
For two-variable linear equations (e.g., 2x + 3y = 6), the solution is the point (x, y) where the two lines representing the equations intersect on a graph.
-
Linear Equation in Two Variables
A linear equation in two variables has the form:
ax + by = c
Where:
-
, , and are constants,
-
and are variables.
The solution to this equation is any pair of values for x and that makes the equation true. For example, the equation 2x+3y=6 has many solutions such as (x = 0, y = 2), (x = 3, y = 0), etc.