Prove theorems about triangles. Theorems include: measures of interior angles of a triangle sum to 180°

base angles of isosceles triangles are congruent; the segment joining midpoints of two sides of a triangle is parallel to the third side and half the length; the medians of a triangle meet at a point.

Popular Tutorials in Prove theorems about triangles. Theorems include: measures of interior angles of a triangle sum to 180°

What is the Hypotenuse-Leg Congruence Theorem?

There's a special theorem that helps you quickly figure out if two right triangles are congruent. This tutorial introduces you to that theorem and shows you how to use it!
How Do You Use the Centroid to Find Segment Lengths in a Triangle?

When you're given the centroid of a triangle and a few measurements of that triangle, you can use that information to find missing measurements in the triangle! This tutorial shows you how it's done.
How Do You Use the Hinge Theorem to Compare Side Lengths in Two Triangles?

The Hinge Theorem helps you compare side measurements of two triangles when you have two sets of congruent sides. Follow along with this tutorial to see this theorem used to find the relationship between the sides of two triangles.
How Do You Write an Indirect Proof?

This tutorial looks at using an indirect proof to show that an equilateral triangle cannot have a right angle.
How Do You Put the Sides of a Triangle in Order According to Size if You Know Two Angles of the Triangle?

Trying to figure out which side of a trianlge is the shortest? How about the longest? All you need to get your answer are the angle measurements of the triangle! How does it work? Watch this tutorial to find out!
What is the Circumcenter of a Triangle?

This tutorial explains the ins and outs of the circumcenter of a triangle. You'll see how to build up from the Perpendicular Bisector Theorem to find the circumcenter of a triangle.
What is the Incenter of a Triangle?

The incenter of a triangle deals with the angle bisectors of a triangle. This tutorial shows you how to find the incenter of a triangle by first finding the angle bisectors.
What is the Hinge Theorem?

What's the Hinge Theorem all about? Watch this tutorial to find out!
What is the Triangle Midsegment Theorem?

The triangle midsegment theorem looks at the relationship between a midsegment of a triangle and the triangle's third side. Follow along with this tutorial to learn about the triangle midsegment theorem.
What is a Median of a Triangle?

A median of a triangle is a special line segment that connects two pieces of a triangle. This tutorial introduces you to the median of a triangle and shows you how many medians each triangle has!
What is the Triangle Sum Theorem?

When you're dealing with triangles, the Triangle Sum theorem can be very useful in finding interior angle measurements. In this tutorial, learn how to find this helpful theorem!