Pupils investigate the number of points needed to determine a unique circle in a plane. Using Cabri Jr., they apply construction techniques to generate a circle that passes through a given number of points.
9th - 12th Math 3 Views 1 Download CCSS: Designed
Construct an Equilateral Triangle (part 2)
Triangles, triangles, and more triangles! In this second installment of a 36-part series, your young mathematicians explore two increasingly challenging constructions, requiring them to develop a way to construct three triangles that...
9th - 10th Math CCSS: Designed
Inscribing and Circumscribing Right Triangles
High schoolers attempt an assessment task requiring them to find the radii of inscribed and circumscribed circles of a right triangle with given dimensions. They then evaluate provided sample responses to consider how to improve their...
9th - 12th Math CCSS: Designed
New Review Special Triangles and the Unit Circle
Calculate exact trigonometric values using the angles of special right triangles. Beginning with a review of the unit circle and trigonometric functions, class members use their knowledge of special right triangles to find the value of...
11th - 12th Math CCSS: Designed
Congruence, Proof, and Constructions
This amazingly extensive unit covers a wealth of geometric ground, ranging from constructions to angle properties, triangle theorems, rigid transformations, and fundamentals of formal proofs. Each of the almost-forty lessons is broken...
8th - 10th Math CCSS: Designed
The unit circle definition of trigonometric function
In this video, Sal shows how the sine and cosine of an angle are defined on the unit circle. He inscribes a 30-60-90 triangle in the unit circle and explains how one can use SOH-CAH-TOA to find the coordinates on the circle.
9 mins 10th - 12th Math