How do I solve quadratic equations

There are multiple ways to do this: by factoring, graphing, or using the quadratic formula.

Combine all of the like terms and move them to one side of the equation. The first step to factoring an equation is to move all of the terms to one side of the equation, keeping the x2 term positive. To combine the terms, add or subtract all of the x2 terms, the x terms, and the constants (integer terms), moving them to one side of the equation so that nothing remains on the other side. Once the other side has no remaining terms, you can just write "0" on that side of the equal sign. 
An example :
2x2 - 8x - 4 = 3x - x2 =