Posted by stacey on .
8. When constructing a perpendicular bisector, why must the compass opening be greater 1/2 than the length of the segment?

math 
Ms. Sue,
http://www.sonoma.edu/users/w/wilsonst/courses/math_150/cs/PerpBisect.html

math 
stacey,
i don't get it

math 
stacey,
can you explain it to me

math 
Ms. Sue,
I can't explain it any better than that web site. What is it that you don't understand?
Or try this site.
http://www.mathsisfun.com/geometry/constructlinebisect.html 
math 
stacey,
i don't get why the compass has to be open more than 1/2 the length segment

math 
Ms. Sue,
Get a compass and try it.
How else are you going to get arcs above and below the line? 
math 
stacey,
so i would answers it like....
the reason that the compass opening has to be greater than 1/2 of the segment is so it can make arcs. 
math 
Ms. Sue,
That's a good start. Continue 

math 
stacey,
i don't know how to finish it

math 
Ms. Sue,
Where do the arcs have to cross?

math 
stacey,
in the middle

math 
Ms. Sue,
Right.

math 
stacey,
so now it would be
the reason that the compass opening has to be greater than 1/2 of the segment is so it can make arcs. and the arcs would have to cross in the middle so that when go to draw the line it would be straight. 
math 
Ms. Sue,
Yay! You're right!

math 
stacey,
thank you

math 
Ms. Sue,
You're welcome.