Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: F Tf Trigonometric Ratios and the Pythagorean Theorem

For Teachers 9th - 10th Standards
The purpose of this task is to use the Pythagorean Theorem to establish a fundamental trigonometric identity for an acute angle. The reasoning behind this identity is then applied to calculate a cosine for a given obtuse angle. Aligns...
Unit Plan
Khan Academy

Khan Academy: Pythagorean Theorem Challenge

For Students 7th - 8th Standards
In this exercise, students practice using the Pythagorean Theorem in word problems. Students receive immediate feedback and have the opportunity to watch a video, get hints, or try questions repeatedly.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 8.g a Rectangle in the Coordinate Plane

For Teachers 8th Standards
In this task, 8th graders are shown a picture of a quadrilateral on a coordinate grid and are asked to use the Pythagorean Theorem to find lengths and to explain why the quadrilateral is a rectangle. Aligns with 8.G.B.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Gpe Squares on a Coordinate Grid

For Teachers 9th - 10th Standards
The purpose of this task is to use the Pythagorean Theorem and knowledge about quadrilaterals in order to construct squares of different sizes on a coordinate grid. Aligns with G-GPE.B.7.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 8.g Area of a Trapezoid

For Teachers 8th Standards
Eighth graders are given various dimensions of a trapezoid and are asked to find its area. This requires them to use the Pythagorean Theorem and to decompose the trapezoid into other polygons. Aligns with 8.G.B.7.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: F Tf Special Triangles 1

For Teachers 9th - 10th Standards
Using known facts about the unit circle and isosceles triangles together with the Pythagorean Theorem, students can derive the sine and cosine of special angles. Aligns with HSF-TF.A.3.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: F Tf Special Triangles 2

For Teachers 9th - 10th Standards
Using known facts about the unit circle and isosceles triangles together with the Pythagorean Theorem, students can derive the sine and cosine of special angles. Aligns with HSF-TF.A.3.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Srt, G Mg How Far Is the Horizon?

For Teachers 9th - 10th Standards
Some friends are at the beach looking out onto the ocean on a clear day and they wonder how far away the horizon is. A second problem asks how far the horizon would be from the top of a mountain. Students must also answer a question...
Unit Plan
CK-12 Foundation

Ck 12: Trigonometry: Lengths of Sides in Isosceles Right Triangles

For Students 10th - 12th Standards
[Free Registration/Login may be required to access all resource tools.] Here you'll learn what an isosceles right triangle is, the relationships between the sides of an isosceles right triangle, and how to find the length of an unknown...
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G C, G Srt Neglecting the Curvature of the Earth

For Teachers 9th - 10th Standards
Jerry and Ashley are trying to find out if it is possible to see the lowest point in the USA from the highest point in the USA. It turns out that the highest point in the United States, the peak of Mount Whitney, is only 85 miles from...