07+-+Solving+Quadratic+Equations+(The+Square+Root+Method)

The standard form of a quadratic equation is expressed this way: 

There are many ways to solve a quadratic equation, how do you know when it's best to use one method over another? For the square root method, the answer is easy: The square root method of solving quadratic equations is especially useful when there is no linear term (when b=0). That is to say, when there is a square term and a constant, but no -term. We'll also see some simple variations on that idea to make that method even more useful.

For example, consider the equation  There is no linear term, just the square term and a constant. Here's how it's done: 

Sometimes isolating the square term is a bit more complicated. There may be multiple steps involved. This next one requires two steps to isolate the square term. 

We can also do this when the coefficient and/or constant is a fraction: 

The square root method is also very convenient when we have a binomial that's being squared and a constant. We'll solve that type of equation with three steps: The first two are the same two as before:

Now it's time to practice what we've seen. You try these. If you have problems, just watch the video below (coming tomorrow):