Curated OER
Math Club #24: Magic Shapes
In this magic shapes worksheet, 7th graders work in groups to solve 9 magic square puzzles requiring logic and problem solving.
CK-12 Foundation
Ck 12: Geometry: Trigonometric Ratios With a Calculator Grades 9 10
[Free Registration/Login may be required to access all resource tools.] This concept teaches students to find trigonometric ratios with a calculator in order to find missing sides of right triangles.
Alabama Learning Exchange
Alex: Geometric Mean and Indirect Measurement
In this inquiry-based lesson, students will work in groups to gather measurements needed to approximate the height of a building. Students will discover how geometric mean can be used to find the lengths of missing sides of right...
Lawrence Hall of Science
The Math Page: Skill in Algebra: The Pythagorean Theorem
Here is a site that clearly and thoroughly explains the Pythagorean Theorem from solving for missing sides of a right triangle through its proof. There are example problems solved, problems for the student to attempt, and answers to the...
Khan Academy
Khan Academy: Use Pythagorean Theorem to Find Isosceles Triangle Side Lengths
Find the missing side lengths of isosceles triangles by using the Pythagorean Theorem. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or receive hints.
Math Is Fun
Math Is Fun: Solving Triangles
Find guidelines to help you "solve" triangles, which means finding the value of missing sides and angles. Provided are examples of six scenarios in which you can solve a triangle's missing measurements, as well as relevant equations,...
Khan Academy
Khan Academy: Solve Similar Triangles (Basic)
Given two similar triangles and some of their side lengths, find a missing side length. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Solve Similar Triangles (Advanced)
Given two similar triangles and some of their side lengths, find a missing side length. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Solve Similar Triangles (Basic)
Given two similar triangles and some of their side lengths, find a missing side length.
Purple Math
Purplemath: Inverses of Trigonometric Ratios
You know that you can take side lengths and find trig ratios, and you know you can find trig ratios (in your calculator) for angles. What is missing is a way to go from the ratios back to the original angles. And that is what "inverse...
Khan Academy
Khan Academy: Use Pythagorean Theorem to Find Area and Perimeter
Find the area and perimeter of triangles and quadrilaterals by first using the Pythagorean Theorem to find missing side lengths. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or...