What is a Quadratic Equation? | Printable Summary

Quadratic equations must have an x² term and cannot have a degree higher than 2
A quadratic equation doesn't necessarily have to have an x term or a constant, as long as it has an x² term

1. If a is equal to 0, then the equation will not have an x² term
2. Quadratic equations cannot have any terms with exponents larger than 2
1. Quadratic equations must be set equal to 0 and must have an x² term
2. Quadratic equations don't necessarily have to have an x term or a constant, as long as they have an x² term
3. Even if an equation is not set equal to 0 at first, as long as you can set it equal to 0 and it ends up in the correct form, it's still a quadratic equation
1. Equations that do not have an x² term are NOT quadratic equations
2. Equations that have a degree higher than 2 are also NOT quadratic equations, even if they do have an x² term
1. You can solve quadratic equations either graphically or algebraically
1. To solve by graphing, first graph your quadratic equation
2. Then look for the zeros of the function - where the graph crosses the x-axis
3. These points will be where y is equal to 0 and give the values of x that make the equation equal to 0
1. Sometimes it's hard to find solutions to an equation on a graph
2. So you can also solve by factoring, completing the square, or using the quadratic formula