Geometry Honors Unit 2: Intro to Geometry 1.6 Coordinate Plane, Midpoint, Distance 1.4 Measuring segments and angles

Agenda

1.  HW Check – Please have it out when the bell rings!!!!

2.  Warm-Up 3.  1.6 Distance/Midpoint 4.  1.4 Measuring segments and angles 5.  Homework

Homework Check

Using horizontal and Vertical Lines only: How far is point A from point B?

Is this the Shortest

Distance?

How many ways Can I find the

Shortest distance?

Distance:

**Remember: AB = distance between A and B** AB = length of

= segment between A and B (Notation)

Distance: on a # line: on a coordinate plane: Pythagorean Theorem or in 3-d:

Examples:

1. Find RS for R(2,3) and S(-4,7)

4. Find ST for S(2, 3, 4) and T(-1, 3, 2).

What value is in the middle of A and B?

Midpoint: the value in the middle of a segment

On a # line: On a coordinate plane: In 3-d:

2. Find the coordinates of the midpoint of where R(2,3) and S(-4,7).

3. Find the coordinates of the midpoint ST for S(2, 3, 4) and T(-1, 3, 2).

1-4 Measuring Angles

Angle: is formed by two rays with the same endpoint.

The rays are the SIDES of the angle. The endpoint is the VERTEX of the angle.

EX NAMES:

Protractor Postulate

m<COD =

Acute Angle

Measures greater than and less than

Right Angle

Measures exactly

Obtuse Angle

Measures greater than and less than

Straight Angle

Measures exactly

Adjacent Angles

Angles that are beside each other and share a common ray as one of their sides.

______ and _______ are adjacent angles.

Linear Pair Are adjacent angles whose non-common sides

are opposite rays. Opposite Rays: A Linear Pair is:

**If two angles are a linear pair, then their sum is

Congruent Angles

Are angles that have the same measure.

Angle Addition Postulate

Angle Bisector Is a ray that divides an angle into two angles. ____ bisects _____, therefore ______________

Examples: 1. 2. 3.

3-d Coordinate Plane! Find the coordinates for: O N K J M H L I

Mini-Project!

� Will count as 3 classwork grades � Distance and Midpoint Trip � Due Tuesday, Sept 18 – Test day – Can

turn in early at any point

Homework

Worksheet