Algebra 1 Roots In Reverse
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Roots II
Roots In Reverse

 

 So now we can deal with stuff like ...

 

X2 = 64

 
 What about stuff like this?
 

 
 Can we solve this one for X?
 
 Sure. 
 In fact, 
 we can do it a couple of different ways ...
 
 FIRST WAY
 We know that ...
 

 
 So if ...
 

 
 We just substitute in the 6 ...
 

 
 So X equals 36.
 
 That way works really nice 
 when the problems are easy.
 
 But sometimes we need another way.
 
 Remember that we can do most anything we want
 on one side of the =
 as long as we do the same thing to the other side.
 
 So here's what we do ...
 

 
 We put an exponent of 2 on everything
 on each side of the equation.
 
 If we write out each side with multiplication
 instead of exponents,
 we get ...
 

 
 The same answer, 
 wonderful !
 
 Here's a very important point that you should see ...
 

 
 We can also show why ...
 

 
 Wanna see?
 
 No?
 
 Well here it is anyway ...
 
 Just what does that last thing say?
 

 
 So what times itself equals X 2?
 

X

 

   copyright 2005 Bruce Kirkpatrick

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