### 1-3 Midpoint Formula

```Warm Up
Find the values of y by substituting
x = 2, 3, 10
1. Y = 20x + 4
2. Y = 9(x+3)
Today’s Objective
SWBAT use the midpoint formula in order
to find the midpoint of a segment.
Homework: Pg 61 #9-19 Odd (15-19 odd
just find the midpoint)
To identify basic shapes and figures in
Geometry
Warm Up
√
Homework: Pg 61 #9-19 Odd
Anticipatory Set
Vocabulary
Midpoint Formula
Distance Formula
Closure
Homework
To identify basic shapes and figures in
Geometry
Warm Up
√
Homework: Pg 61 #9-19 Odd√
Anticipatory Set
Vocabulary
Midpoint Formula
Distance Formula
Closure
Anticipatory Set
Fold a segment bisector activity
Draw AB on a piece of paper, fold the paper
so Point B is on top of Point A
The point where the crease intersects the
line is the mid-point
Label this point M
What do we notice when we compare
AM to MB?
To identify basic shapes and figures in
Geometry
Warm Up
√
Homework: Pg 61 #9-19 Odd√
Anticipatory Set √
Vocabulary
Midpoint Formula
Distance Formula
Closure
Vocabulary
1. Midpoint
2. Segment Bisector
Midpoint
The point that divides a segment into 2
congruent segments.
E
F
These tick marks
signify that both of
these segments
are congruent
G
Segment Bisector
A point, ray, line, line segment, or plane,
that intersects the segment at its midpoint.
E
E
F
G
E
G
G
E
G
To identify basic shapes and figures in
Geometry
Warm Up
√
Homework: Pg 61 #9-19 Odd√
Anticipatory Set √
Vocabulary √
Midpoint Formula
Distance Formula
Closure
Midpoint Formula
 The coordinates of
the midpoint of a
segment are the
averages of the xcoordinates and the
y-coordinates
 X 1  X 2 Y1  Y 2 
,


2
2 

Find the Midpoint
The endpoints of RS are R(1, -3) and
S(4,2). Find the midpoint M of RS.
The midpoint of JK is M(2,1). One
endpoint is J(1,4). Find the endpoint K.
To identify basic shapes and figures in
Geometry
Warm Up
√
Homework: Pg 61 #9-19 Odd√
Anticipatory Set √
Vocabulary √
Midpoint Formula √
Distance Formula
Closure
Distance Formula
 The distance formula
for finding the length
between 2 points is:
( X 2  X 1 )  (Y 2  Y1 )
2
2
Find the distance between 2 points,
round to the nearest tenth of a unit
P(1,2) and Q(5,4)
Q(-3,5) and R(2,3)
Let’s Review the Vocabulary
 M is the midpoint of VW. Find
the length of VM.
V
4x-1
M
3x+3
W
```