Building blocks

Midpoints and congruent segments

Congruent segments:
Segments are congruent if they have the same measure.

If the lengths of

and

are each 9 inches, then

(The symbol

is read as "is congruent to").

Midpoints:
The midpoint of a line segment is the point that divides the segment into two congruent segments.

If M is the midpoint of , then:

If Z is the midpoint, find and

3y-1=6y-4
-1+4=6y-3y
3=3y
y=1

Then = 3(1)-1=3-1=2, =2 units.

= 3y-1+6y-4 = 9y-5 = 9(1)-5 = 9-5 = 4, =4 units.

If =20, C is the midpoint of , and D is the midpoint of , find

=5 units