**Title:** Geometry Pad App

**Description:**
Create geometric shapes, explore/change their properties, and calculate metrics.

**Standard(s): **

[MA2013] GEO (9-12) 1: Know precise definitions of angle, circle, perpendicular line, parallel line, and line segment based on the undefined notions of point, line, distance along a line, and distance around a circular arc. [G-CO1]

[MA2013] GEO (9-12) 28: Derive, using similarity, the fact that the length of the arc intercepted by an angle is proportional to the radius, and define the radian measure of the angle as the constant of proportionality; derive the formula for the area of a sector. [G-C5]

[MA2013] GEO (9-12) 38: Identify the shapes of two-dimensional cross-sections of three-dimensional objects, and identify three-dimensional objects generated by rotations of two-dimensional objects. [G-GMD4]

[MA2013] GEO (9-12) 39: Use geometric shapes, their measures, and their properties to describe objects (e.g., modeling a tree trunk or a human torso as a cylinder).* [G-MG1]

[MA2013] ALT (9-12) 37: Understand radian measure of an angle as the length of the arc on the unit circle subtended by the angle. [F-TF1]