read and answer each.
1.How do you think zero came into being?
Because quantities were thought of as either distances
traveled or corresponding to distances traveled and to
travel a distance, you always need a starting place, and
zero is that starting place
2. Why is there a need for negative numbers?
To indicate a distance traveled in the reverse direction.
If positive numbers indicate travel to the right, negative
numbers indicate travel to the left. If positive numbers
indicate gain, negative numbers can indicate loss.
3.Give an example where a rational number is used?
rds of 6 is 4. is a rational number
because it is the quotient of two integers. Incidentally
6 and 4 are also rational numbers because 6 can be written
as 
and 4 can be written as 
and both of
those are quotients of two integers.
4.What lessons in the previous grades do you remember using irrational numbers?
a. Wnen using the Pythagorean theorem, we often found the
sides of right triangles which were square roots of
integers that were not perfect squares. For instance
if the two legs of a right triangle are 2 and 3, the
hypotenuse is 
= 
= 
.
is an irrational number.
b. When we were finding the circumference of a circle, we
used the number 
, which is an irrational number.
5.Why is 0.5 a rational number?
Because 0.5 is equal to 
which is the quotient of two
integers.
Edwin
