geometry georgia performance standards jan munroe jmunroe@forsyth.k12.ga.us sawnee elementary school...

Geometry

Georgia Performance Standards

Jan Munroejmunroe@forsyth.k12.ga.usSawnee Elementary SchoolForsyth County Schools

Angles

An angle is formed by 2 rays or 2 line segments that share the same endpoint.

Angle formed by two rays

Angle formed by2 segments

The endpoints where the rays or segments meet is called the vertex of the angle. The rays or segments are called the sides of the angle.

Classifying Angles

A right angle measures 90 degrees.

An accute angle measures between 0 and 90 degrees.

An obtuse angle measures between 90 and 180 degrees.

A straight angle measures 180 degrees

A reflex angle measures between 180 and 360 degrees.

Angles may be classified according to size. Use the protractor tool to measure the angles below.

A right angle measures 90 degrees.

An accute angle measures between 0 and 90 degrees.

An obtuse angle measures between 90 and 180 degrees.

A straight angle measures 180 degrees

A reflex angle measures between 180 and 360 degrees.

Now let's check for understanding. Use the spotlight tool to identify the angles below as the names are called. Then drag away the yellow to reveal the answers!

Use the spotlight tool to locate the right, acute, obtuse, reflex and straight angles in the illustation below.

A

B

C

D

EF

G

Parallel and Perpendicular Lines

Parallel lines are lines on a flat surface that never meet. They are always the same distance apart.

Perpendicular lines are lines that intersect or cross and form right angles.

Triangles are the simplest type of polygons. The prefix tri means three. Triangles have 3 vertices, 3 sides,and 3 angles.

Equilateral Triangle

Isosceles Triangle

ScaleneTriangle

Right Triangle

All sides and angles are equal.

Has one right (90 degree angle).

Has two equal sides and two equal angles.

Has no equal sides and no equal angles.

Isosceles Triangles Right Triangles

Scalene Triangles Equilateral Triangles

Drag the triangles at the bottom of this page to the boxes in which they belong!

A quadrangle is a polygon that has 4 sides. Another name for quadrangle is quadrilateral. The prefix "quad" means four. All quadrangles have 4 sides, 4 vertices and 4 angles.

Quadrangles with 2 pairs of parallel sides.

Square

Has 4 equal sides and 4 equal angles.

Rectangle

Opposite sides are equal.

Parallelogram

Trapezoid

Rhombus

All sides may have different lengths and angles may be different.

Opposite corners of a square are pulled in opposite directions.

Trapezoid Parallelogram

Rectangle Square

Check for Understanding

____ 1. Which one of the following figures is a trapezoid?

____ 2. Which one of the following figures is a right angle?

____ 3. Which one of the following figures is a parallelogram?

A. B. C.

A. B. C.

C.B.A.

Check for Understanding

____ 4. Which one of the following figures is an equilateral triangle?

____ 5. Which one of the following figures is an example of parallel lines?

____ 6. Which one of the following figures is an acute angle?

A. B. C.

A. B. C.

C.B.A.

Use the voter button to select the correct answer.

1. A right angle measuresA. 180 degreesB. between 0 and 90 degreesC. 90 degrees

2. A reflex angle measuresA. between 180 and 360 degreesB. between 90 and 180 degreesC. 180 degrees

3. A straight angle measuresA. 90 degreesB. between 90 and 180 degreesC. 180 degrees

4. Acute angles measureA. between 180 and 360 degreesB. between 0 and 90 degreesC. between 90 and 180 degrees

Use the voter button to select the correct answer.

6. Lines or line segments that never meet and are always the same distance apart are called A. intersecting lines

B. parallel linesC. perpendicular lines

7. Lines or line segments that cross and form right angles are called A. intersecting lines

B. parallel linesC. perpendicular lines

8. Lines or line segments that cross each other are called A. intersecting lines

B. parallel linesC. perpendicular lines

10. A triangle with one right angle is calledA. a scalene triangleB. an equilaterial triangleC. a right triangle

11. A triangle that has no equal sides is calledA. a scalene triangleB. an equilateral triangleC. a right triangle

Use the voter button to select the correct answer.

12. A quadrilateral that has two pairs of parallel sides is calledA. a trapezoidB. a kiteC. a parallelogram

13. A quadrangle with 1 pair of parallel sides and may have different lengths for all sides is called A. a trapezoidB. a kiteC. a parallelogram

14. Quadrangles that are parallelograms areA. trapezoids and kitesB. rectangles, rhombuses and squaresC. cubes and trapezoids

Credits

Bell, M. (et.al.). Everyday Mathematics. The University of Chicago School Mathematics Project. Everyday Learning: Chicago, Illinois,

2002.