An informative lesson contains a brief explanation of how the sum of the angles of a triangle is a line. The lesson continues with determining the missing angle in a triangle, or solving for a variable. Using the sum of the...

You've heard that it is true, but can you prove it? Scholars learn the Pythagorean Theorem through proof. After an overview of proofs of the theorem, learners apply it to prove triangles are right and to problem solve. This is the second...

Word problems can make even expert mathematicians go blank. Practice solving word problems with an extended version of the GUESS method (givens, unknowns, equations, solve, substitute), which adds the steps of drawing a diagram, making...

There isn't a more popular geometry formula than the Pythagorean Theorem! Learners understand the special side relationships in a right triangle. They use the Pythagorean Theorem to find missing sides and to solve problems. They begin...

Use patterns to your advantage! The Pythagorean Theorem allows learners to find missing sides of right triangles. Problems include those with both rational and irrational lengths. 

Find the shortest distance from A to B using the Pythagorean Theorem! Scholars learn they can find the distance between two points by creating a right triangle using the horizontal and vertical lengths and applying the Pythagorean...

The shortest distance between two points is a straight line. Learners use the Pythagorean Theorem to develop a formula to find that distance. They then find the midpoint using an average formula. 

Lateral area and surface area are simple concepts, but calculating them is not as easy! Using formulas, learners calculate lateral area and surface area for the same three-dimensional figures. The resource discusses the formula variables...

You'll be spinning in unit circles once you read through this jumbo-sized resource of everything you need to know about trigonometry. Each page has color-coded examples with explicit directions that detail the problems and...

Investigate how similar and congruent figures compare. Learners understand congruent figures have congruent sides and angles, but similar figures only have congruent angles — their sides are proportional. After learning the...

Explains the basic concept of equilateral triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.

Explains the basic concept of triangle inequalities with step-by-step instructions and methods for solving specific problems on your own relating to this topic.

Explains the basic concept of similar triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.

Explains the basic concept of congruent triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.

Explains the basic concept of triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.

Explains the basic concept of right triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.

Explains the basic concept of isosceles triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.

Demonstrates how to translate, set up, and solve basic right-triangle word problems.

This comprehensive guide explores the topic of sine law, by finding answers to questions like what is the law of sines, what are the applications of sine law, and proof of the sine law. Includes solved examples and practice questions.

Demonstrates how to use trig ratios to do simple solving of triangles.

College professor Dan Bach reviews basic trig concepts, including trig functions, right triangles, circles, radians, and polar coordinates. Site includes animated graphs and detailed examples.

Explains the basic concept of the Pythagorean Theorem with step-by-step instructions and methods for solving specific problems on your own relating to this topic.

Provides a detailed definition of the Hinge Theorem with step-by-step instructions and methods for solving problems on your own.

Explains the basic terminology and formatting of ratios, and demonstrates how to solve typical exercises.