and factoring. What are the pros and cons of each of these methods? When might each method be most appropriate? Which method do you prefer? Why?

February 6th, 2011 @1:11 am

I like using the quadratic formula because it’s easy just to plug in those numbers, especially with a calculator, and before you know it you’ll memorize the formula.

February 6th, 2011 @1:13 am

The quadratic formula is by far the best because it gives you the exact solution (i.e. 1+sqrt(2) instead of just 2.414 which is what you would get if you graphed it). Also, graphing will not show you imaginary roots which the quadratic forumla will. I would recommend writing a program in your calculator (way easier then it sounds) which will solve the equation based on inputs of a, b , and c. If you set the mode to a+bi, then it will even tell you the imaginary roots.

If the factorization is obvious, I prefer that. If b^2 – 4ac is less than zero, the quadratic formula is a must. Graphing is my last choice since that is not exact unless you are using a graphing calculator. Even then, it can be just an estimate.