2. What is a quadratic equation?
The name quadratic zome from “squad” meaning
square, the variable get squared (over 2)
The standard form of a quadratic equation is:
ax´2 + bx + c
The assumptions are:
a, b and c are known values. a can't be 0.
"x" is the variable or unknown (you don't know it
yet).
4. How to solve quadratic equations
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 special Quadratic Formula:
5. Solving quadratic equations by
factorizing
Having an easy quadratic formula, factorizing become
a easy and fast method:
Having: x2 + 10x + 25
Can factorized as (x+5) (x+5)
Now by making each equation equal “0”
X+5 = 0, x = -5
6. Solving by complete the square
Completing the square is used when the equations
doesn’t have a “c” value
Having: x2 + 4x + 1 = 0
The equation cannot be factorizing therefore is
necesarry complet the square
7. Step 1: Passing to the other side the “c” value
x2 + 4x = -1
Step 2: Using the formula (B/2)2 obtain the real “c”
value
(4/2)2 = 4
Step 3 : Sum the “c” value to both sides of the equation.
x2 + 4x + 4 = -1+ 4
Step 4: Factorize the trinomial equation
(x+2)2 = 3
Solve the quation by square root
8. Solving by the quadratic formula
In order to solve difficult equations, quadratic formula
is used:
It is used by substituting each value: a, b and c
according to the equation given.
9. *Completing the Square (Completing the Square)
http://www.mathsisfun.com/algebra/completing-square.html
*Quadratic equations. (2000, January 1). . Retrieved May 29, 2014,
from http://mathworld.wolfram.com/QuadraticEquation.html