University of Adeaide
Basic Trigonometry and Radians
A fabulous set of examples and problems that introduce basic trigonometry concepts, this packet is set apart by the care it takes to integrate both radians and degrees into the material. After defining radians, the author demonstrates...
Illustrative Mathematics
Two Wheels and a Belt
Geometry gets an engineering treatment in an exercise involving a belt wrapped around two wheels of different dimensions. Along with the wheels, this belt problem connects concepts of right triangles, tangent lines, arc length, and...
Curated OER
Circles: Geometry Review Worksheet
Tenth graders solve and complete 14 different geometry problems. First, they find the area and circumference of a circle with a given radius. Then, they find the area between a circle and an inscribed equilateral triangle given the...
Curated OER
Radian Measure
Young mathematicians identify central angles, arcs and radius of circles in this pre-calculus lesson plan. They identify the proportion of the circle based on its radius while they convert between degrees and radians measurements.
Curated OER
Arc Length and Sectors
Find the length of an arc. Students relate central angles to the area and length of a sector and graph circles on the TI to make predictions.
Curated OER
Reference Angles
Learn how to measure the reference angles in degrees and radians. Students find reference angles that are coterminal with a given angle.
Texas Instruments
Area of Circles
Students explore circles. In this algebra/geometry lesson, students discover the formula for the area of a circle, as they investigate the ratio of the area of a circle to the radius^2.