Quadratic Equations is Fx² + Ux + N
Definition – Quadratic equation is an equation in which the highest power of an unknown quantity is a square. It is a polynomial equation of the second degree.
What does it look like?
A ‘standard’ quadratic equation
ax² + bx + c = 0
Let’s break it down
- The letters a, b and c are coefficients (you know those values). They can have any value, except that a cannot be 0. [Remember a coefficient is a number before a variable, x is the variable. It is unknown]
- The letter “x” is the variable (you don’t know the value as yet)
Here is an example of one:
Give explanation as to why it is called a quadratic equation when it is only raised to the 2nd power. (Hint: word origination)
The solutions to the Quadratic Equation are where it is equal to zero. There are usually 2 solutions to the equation.
They are also called “roots”, or sometimes “zeros”
There are 3 ways to find the solutions:
1) You can factor the Quadratic (find what to multiply to make the Quadratic Equation)
2) You can complete the Square
3) You can use the Quadratic Formula:
It is read “minus b plus or minus the square root of b-squared minus four ac, all over two a”
The entire formula can now be explained. The following website gives conceptual information in a fun way.
Quadratic Rap – would no longer forget formula
Project and Exercise- use link
Using the Quadratic Formula solve the following problem
Just put the values of a, b and c into the quadratic Formula and, do the calculations, also graph the equation.
5x² + 6x+ 1= 0