| 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: | ||
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3 time X equals 3X |
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| Hey, that's not too bad is it? | ||
| That trick works with ANY letter so: | ||
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2 × G = 2G |
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5 × B = 5B |
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.5 × Z = .5Z |
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| This trick even works with 2 or more letters: | ||
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X × Y = XY |
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B × I × G = BIG |
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A × L = AL |
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| We can do division with letters too! | ||
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| But we don't get far with addition or subtraction: | ||
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3 - X = 3 - X |
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A + B = A + B |
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| We know that: | ||
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32 = 3 × 3 |
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| So it should be no big surprise that: | ||
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W2 = W × W |
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| Examples: | ||
| Simplify: 3 × X × Y × Z × Z | ||
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3XYZ2 |
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| Simplify: 2 × A × A × B × B ÷ C | ||
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| 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 | ||
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24XY |
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| 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 | ||
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2A2 - B2 |
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copyright 2005 Bruce Kirkpatrick |
