4.MD.5

Recognize angles as geometric shapes that are formed wherever two rays share a common endpoint and understand concepts of angle measurement.

Lesson 4.MD.5

Concepts addressed:

• Recognize angles as geometric shapes that are formed wherever two rays share a common endpoint and understand concepts of angle measurement

• Understanding an angle is measured with reference to a circle with its center at the common endpoint of the rays, by considering the fraction of the circular arc between the points where the two rays intersect the circle

• An angle that turns through 1/360 of a circle is called a “one-degree angle,” and can be used to measure angles.

• Understanding an angle that turns through n one-degree angles is said to have an angle measure of n degrees.

Key terms for this lesson:

• Angle - the space (usually measured in degrees) between two intersecting lines or surfaces at or close to the point where they meet.

• Polygons - a figure with at least 3 sides and 3 angles, on top of that, it cannot have any curved sides

• Quadrilaterals - shapes that have four sides and four right angles

• Point - a point in geometry is a location. It has no size i.e. no width, no length and no depth. A point is shown by a dot.

• Line - a line can be defined as a straight one-dimensional figure that has no thickness and extends endlessly in both directions.

• Line segment - a line segment is a piece or part of a line having two endpoints. Unlike a line, a line segment has a length.

• Ray - a ray is a line with a single endpoint

Common angle measures in geometry!

This worksheet went over:

Additional practice:

Lesson Complete!