Frequently Asked Questions: This page contains answers to common questions of students and parents.

1. Yo yo yo, 'sup, G?
2. Why do we find slope by using rise over run and not run over rise?
3. What is the meaning of life?
4. What does E=mc squared mean?
5. How do I pronounce "FAQ" so that the teacher won't think I'm swearing?
6. Whud'up wit' de whole "Han shot first!" thing?

Yo yo yo, 'sup, G?

I put this here because it is a Frequently Asked Question; I hear people asking it all the time!

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Why do we find slope by using rise over run and not run over rise?

I borrowed (stole) this answer from my good friend Dr. Math at 
http://mathforum.org/library/drmath/view/66624.html

There are at least two questions here: 

1)  Why do we define the word  "slope" to mean the ratio of "rise" to 
"run"? and 
2)  Why is that the right number to use in the slope-intercept form of a line?

The answer to the first question is that any number we assign to a "slope" ought to 
be bigger when the line is sloped more steeply. We want the "slope" to tell us how much the line 
is sloped. A steeper line goes up more in the same distance:

        o
       /
      /
     /            o
    /           /
   /          /
  o         o
  steep    less steep

If we used the "run" over the "rise", then the less steep line would have a 
greater slope, which wouldn't make sense:

        o
       /|
      / |
     /  |          o
    /   |        / |
   /    |      /   |
  o-----+    o-----+
    6/6        3/6      <-- actual slope: steeper has greater slope
    6/6        6/3      <-- run/rise: steeper has smaller slope!

How about the question of what goes in the "m" spot in the equation?  Let's look at 
the intercept and one other point on the line:

        |       /
        |     o (x,y)
        |   / |
        | /   |
  (0,b) o-----+
        |
        |
        +---------------

What is the slope of that line?

      y-b   y-b
  m = --- = ---
      x-0    x

If we multiply both sides of the equation by x, we get

  mx = y - b

and adding b to both sides gives

  mx + b = y

So if we define slope as rise/run, then this is the equation that any point on the line has to fit. If 
you defined slope differently, you would get a different equation.

So here's how it works: we define slope in a way that makes sense based on what the word 
"slope" means; then we find that we can use that slope value in an equation that describes any 
point on the line.

One could use a different formula for something like "slope", and get a different 
equation; but this one gives us a reasonable definition AND a nice little equation to use it in.

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What is the meaning of life?

Well, it's nothing very special. Uh, try and be nice to people, avoid eating 
fat, read a good book every now and then, get some walking in, and try and 
live together in peace and harmony with people of all creeds and nations.

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What does E=mc squared mean?

According to Einstein's famous equation E = mc squared, the energy (E) of a 
physical system is numerically equal to the product of its mass (m) and the 
speed of light (c) squared. It is customary to refer to this result as "the 
equivalence of mass and energy"; or simply ";mass-energy equivalence", 
because one can choose units in which c = 1, and hence E = m. An important 
consequence of E = mc squared is that a change in the rest-energy of a 
physical system is accompanied by a corresponding change to its inertial 
mass.  

See?  Easy!

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How do I pronounce "FAQ" so that the teacher won't think I'm swearing?

Sorry, can't help you there!

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Whud'up wit' de whole "Han shot first!" thing?

In the original version of Star Wars, released in 1977, Han Solo blasts 
Greedo, Jabba the Hut's paid killer, before Greedo can draw his gun on him.  
Digital alterations made by George Lucas in the 1997 "20th anniversary" re-
release of Star Wars show Greedo firing a shot first and Han somehow 
miraculously ducking the laserblast coming at him at light-speed, then 
returning fire and killing that slimeball Greedo.

Forget for a moment the ludicrous (that's Ludacris for you hip-hop fans)
possibility that a trained paid killer for the most vile gangster in the 
galaxy could miss his target from less than three feet away; true Star Wars 
fans know that Han Solo is a stone-cold killer who later becomes good by 
joining the Rebellion!  He's not some wimpy milquetoast who'll nicely let a 
bounty hunter take a shot at him before firing back!  He's a ruthless 
smuggler who shoots first in order to survive.  That's the way it is in 
the "hive of scum and villainy" that is Mos Eisley.

So true Star Wars fans, remembering that Solo was a stone-cold killer who 
later redeemed himself and ended up hangin' wit' Leia's too-cool fer old-
school Rebel crew, shout in protest at any opportunity, "HAN SHOT FIRST!"
Any scene showing otherwise is a LIE!

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