Answer:
There are many colored pebbles to choose from out of the driveway. Karmin could not decide what one he wanted for his school project. So he took the best looking 4 from the driveway. 3 of them are now his backups.
You use this tequnic (sorry I can't spell) almost everyday. When ever you think about how much of something to take, you could be using this Pascal Triangle.
I hope this helped.
If you know that 
, then you know right away
###
Otherwise, you can derive the same result. Let 
, so that 
. 
is bounded, so we know 
. For these values of 
, we always have 
.
So, recalling the Pythagorean theorem, we find
Then
as expected.
Option B : The area of the circular base multiplied by the height of the cylinder
If you need to solve this equation you can multiply the both side of equation on (-1). Like that
<span>2 = (-x);
-1·2 = (-1)·(-x)
if you multiply negative and </span><span>positive </span>you'll have negative,
if you multiply negative and <span>negative you'll have </span><span><span>positive. So
</span>
</span>-2 = x. or
x = -2.
The answer is -2.
