Purple Math
Purplemath: Basic Trigonometric Ratios: Examples
Demonstrates how to use trig ratios to do simple solving of triangles.
Khan Academy
Khan Academy: Solve for an Angle in Right Triangles
Given two sides in a right triangle, find one of the acute angles using trigonometry. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Illustrative Mathematics
Illustrative Mathematics: G C, G Srt Neglecting the Curvature of the Earth
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...
Illustrative Mathematics
Illustrative Mathematics: G C, G Srt Setting Up Sprinklers
In this task, students must decide where to place sprinklers on a lawn so that the maximum area of the lawn will be watered. To solve it, they must find areas of sectors of circles and use trigonometric ratios to solve right triangles....
Illustrative Mathematics
Illustrative Mathematics: G Srt Shortest Line Segment From a Point P to a Line L
In this task, students develop an understanding that the shortest path from a point to a line always meets the line at a right angle. Aligns with G-SRT.C.8.
Illustrative Mathematics
Illustrative Mathematics: G Srt, G Mg Coins in a Circular Pattern
In this task, students investigate how many coins will fit around a central coin when they are all of the same denomination, and if there is room left over. The teacher is given a chart of four coin denominations and their diameters, but...
Illustrative Mathematics
Illustrative Mathematics: G Srt, G Mg Seven Circles Iii
In this task, students are shown circle formations where an inner circle is surrounded by a set of circles and all circles are touching. In the first situation, all circles have the same diameter. In the second, the inner circle is...
Illustrative Mathematics
Illustrative Mathematics: G Srt Ask the Pilot
In the July 2013 issue of United Airlines' Hemisphere Magazine, a pilot responded to a question about how far in the distance he could see at different altitudes. The solution involved right triangles, lines of tangency to a circle, and...
CK-12 Foundation
Ck 12: Trigonometry: Lengths of Sides in Isosceles Right Triangles
[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...
CK-12 Foundation
Ck 12: Geometry: Pythagorean Theorem and Pythagorean Triples
[Free Registration/Login may be required to access all resource tools.] Apply the Pythagorean Theorem and its converse. Includes videos, exercises, links to interactive activities, etc.