In this post, we will look at several types of equations that you would encounter when learning algebra. Algebra is a foundational subject to know when conducting most quantitative research.
Equations
An equation is a statement that balances two expressions. Often equations include a variable or an unknown value. By solving for the unknown value you are able to balance the equation.
There are many different types of equations such as
(1) Linear equation
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(2) Quadratic equation
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(3) Polynomial equation
See number 1 or 2. The rule for polynomial equation is that the exponent must be positive
(4) Trigonometric equation
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(5) Radical equation
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(6) Exponential equation
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This post will focus on linear equations.
Linear Equation
A linear equation is an equation that if it is graph will render a straight line. It is common to have to solve for the variable in a linear equation by isolating as in the example below.

There are also several terms related to equations and the include the following
- Conditional equation: An equation that is true for only one value of the variable. The example above is a conditional equation.
- Identity: An equation that is true for any value of a variable. Below is an example

Any value of x will work with an identity equation.
- A contradiction is an equation that is false for all values. Below is an example

No value of x will work with the equation above.
Conclusion
This post provided an overview of the types of equations commonly encountered in algebra.
