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The Square Root Trick

You'll like this section.  It's really easy!

Let's revisit those quadratics with no middle x guy... Like

x^2 - 4 = 0

There are two ways we can solve this guy.

WAY 1:  Our old factoring way:

x^2 - 4 = 0 gives ( x - 2 ) ( x + 2 ) = 0 which gives x - 2 = 0 or x + 2 = 0 which gives x = 2 or x = -2

{ -2 , 2 }

WAY 2:  A new square root trick:

Let me explain it all, then you'll see that it's a really slick way to go.

x^2 - 4 = 0

First, get the  x^2 alone:

x^2 - 4 = 0 ... add 4 to both sides, which gives x^2 = 4