Chapter 16
Muscling Up to Quadratic Equations
IN THIS CHAPTER
Taking advantage of the square-root rule
Solving quadratic equations by factoring
Enlisting the quadratic formula
Completing the square to solve quadratics
Dealing with the impossible
Quadratic (second-degree) equations are nice to work with because they’re manageable. Finding the solution or deciding whether a solution exists is relatively easy — easy, at least, in the world of mathematics.
A quadratic equation is an equation that is usually written as 
, where b, c, or both b and c may be equal to 0, but a is never equal to 0. The solutions of quadratic equations can be two real numbers, one real number, or no real number at all. (Real numbers are all the whole numbers, fractions, negatives and positives, radicals, and irrational decimals. Imaginary numbers are something else again!)
When solving quadratic equations, the ...
Get Algebra I All-in-One For Dummies now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
