What are quadratic equations and how do you solve them?

Question

I've totally forgot how to do these!! Please help!

Yeah, if you could either post links to pages explaining how to solve quadratic equations or explain them out in your answer given the character limit, that would be great. Thanks.

Answer 1

Quadratic equations are of the form:

ax^2 + bx + c = 0 (a not =0)

where a,b, and c are constants.

Solving a quadratic equation means finding the values of a (called the roots) for which the equation is true. The solutions are the values of x where the curve crosses the x axis (y = 0).

The shape of a quadratic curve is a U or upside down U and is called a parabola.

The following methods can be used to solve a quadratic equation:

(1) Construct a graph by choosing a range of values for x and calculating the corresponding value for y. See where the curve cuts the x axis.

(2) By factorisation

(3) By completing the square

(4) Using the quadratic formula

If the curve cuts the x axis twice then there will be 2 solutions. If it touches the x axis then there is 1 solution. If it does not cross the x axis then there are no real solutions.
Did you want details of these methods or is this enough?

Answer 2

quadratic equations are those whose highest power is two.
you can solve quadratic equations in three ways:
1. quadratic formula
2. factoring
3. completing the squares.

i hope this helps...

Answer 3

ax² + bx + c = 0

x = (-b +/- √(b² - 4ac)) / 2a