4.1 Angles and Polygons Lesson

4.1 Angles and Polygons Lessons

Intersecting lines

• cross at some point

Multiple Select

Choose the images that have intersecting lines.

Parallel lines

• are always the same distance apart

• they will never cross

Multiple Select

Choose the images that have parallel lines.

Perpendicular lines

• intersect at a right angle

• a right angle is always 90 degrees

Multiple Select

Choose the images that have perpendicular lines.

Angles

• when two rays meet an an end point

• notice the ray is a line that goes on forever

• an end point is also called a vertex

Acute Angle

• Smaller than 90 degrees

• 
  

• 
  

Multiple Select

Identify all of the acute angles.

Obtuse Angles

• an angle larger than 90 degrees, but less than 180 degrees

Multiple Select

Identify all of the obtuse angles.

Right Angles

• Always 90 degrees

• Often shown with a little square in the angle

Multiple Select

How many right angles are in A?

• 3

• 2

• 1

• 4

Multiple Select

How many right angles are in E?

• 3

• 2

• 1

• 4

Straight Angles

• always measures 180 degrees

• It's basically a straight line. (hence the name)

Multiple Select

Select all of the straight angles.

Reflex Angle

• an angle that is larger than 180 degrees, and smaller than 360 degrees

Multiple Choice

This image shows only reflex angles.

• True

• False

Poll

How did you understand this lesson?