EngageNY
An Area Formula for Triangles
Use a triangle area formula that works when the height is unknown. The eighth installment in a 16-part series on trigonometry revisits the trigonometric triangle area formula that previously was shown to work with the acute triangles....
Curated OER
Pythagorean Theorem: Triangles and Their Sides
Students investigate triangles and their relationship to each other. In this geometry lesson, students solve right triangles using the properties of the Pythagorean Theorem. They differentiate between right, acute, straight and oblique...
EngageNY
Law of Cosines
Build upon the Pythagorean Theorem with the Law of Cosines. The 10th part of a 16-part series introduces the Law of Cosines. Class members use the the geometric representation of the Pythagorean Theorem to develop a proof of the Law of...
Curated OER
Some More Trigonometry
Students define the law of cosine and its correct usage. In this trigonometry lesson, students define the law of Heron's area formula and use it to solve problems. They review other trigonometric values and identify the identities.
Curated OER
Vectors: How Much Force Can You Apply
This activity entails the viewing of two videos to get an overview of force and its application. The activity covers how vectors use force in real-world situations.