Pre Algebra Math With Letters
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Funny Numbers
Math With Letters

 
 Maybe you have heard that Algebra is math with letters. 
 That's partly true. Algebra does use letters. 
 But it also uses numbers, LOTS of numbers. 
 It also still uses all the same rules we've already talked about.
 
 OK, let's do letters:
 

 3 time X equals 3X

 
 Hey, that's not too bad is it?
 That trick works with ANY letter so:
 

 2 G = 2G

 

 5 B = 5B

 

 .5 Z = .5Z

 
 This trick even works with 2 or more letters:
 

 X Y = XY

 

 B I G = BIG

 

 A L = AL

 
 We can do division with letters too!
 

 

 

 But we don't get far with addition or subtraction: 
 

 3 - X = 3 - X

 

 A + B = A + B

 

 
 We know that:
 

 32 = 3 3

 
 So it should be no big surprise that:
 

 W2 = W W

 
 Examples:
 
 Simplify: 3 X Y Z Z
 

 3XYZ2

 
 Simplify: 2 A A B B C
 

 

 
 Example:
 
 If a couple of numbers show up in a problem 
 where everything is multiplied or divided, 
 we can combine the numbers:
 
 Simplify: 3 X Y 4 2
 

 24XY

 

 
 Example:
 
 If we have multiplication and division in a problem with addition or subtraction, 
 we can do the multiplication and division 
 but leave the addition or subtraction alone:
 
 Simplify: 2 A A - B B
 

 2A2 - B2

 

   copyright 2005 Bruce Kirkpatrick

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