Measure angles in whole-number degrees using a protractor

What you'll learn

1. Position a protractor correctly on an angle — center point on the vertex, baseline aligned along one ray — and read the angle measure in whole-number degrees
2. Identify and use the correct scale (inner or outer) on a protractor by determining which scale starts at zero along the baseline ray
3. Sketch an angle of a specified whole-number degree measure by drawing one ray, placing the protractor, marking the target degree, and drawing the second ray through the mark
4. Measure angles presented in non-standard orientations — rays pointing left, downward, or at oblique angles — without repositioning the figure
5. Check the reasonableness of a measurement by classifying the angle first (acute, right, or obtuse) and confirming that the numerical measure matches the classification

Prerequisites

• Recognize angles as geometric shapes that are formed wherever two rays share a common endpoint