Khan Academy: Triangles: Fill in the Blank Triangle Proofs Example 1

Delving into basic trigonometry, this resource shows how to find the area of an inscribed equilateral triangle. Using a high-level problem, HeronÕs theorem is used to find the area of a figure. Before SAT testing, use this as a review.

This video will fill in the blanks in a proof showing that the triangles are congruent.

In this seven-problem quiz/practice, students will calculate whether a point is inside a triangle in 3D.

Students explore a problem that requires then to figure out the area of an equilateral triangle inscribed in a circle using a little trigonometry.

A video lesson that goes through four example problems dealing with conic sections. Topics covered include: finding the vertex of a parabola from its equation; finding the asymptotes of a hyperbola and then sketching its graph;...

Young mathematicians observe a geometric proof using a short video. They see each part of the diagram clearly labeled and the simple math written off to the side. The new knowledge helps them solve additional problems independently.

Explains what it means for two triangles to be similar. Diagram of similar triangles is created with two parallel lines cut by two transversals.

Given two triangles, determine whether they are congruent and use that to find missing angle measures. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

Review the triangle similarity criteria and use them to determine similar triangles.

Find missing angles in isosceles triangles given just one angle. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.