﻿ Circle Proofs Worksheets
The following activity sheets will teach your students how to perform different calculations for circles.

#### A geometric proof is basically a well stated argument that something is true. It provides a step by step reasoning to produce a logical reason for why something is true. If you think about it; we use geometric proofs all of the time. When you go to the grocery store and decide whether it makes sense to buy a bigger box of cereal you think in proofs. If you think proofs are not in involved, somewhere along the line, when engineers and architects present their building projects. They need to prove the construction is not only structurally sound, but worth the millions of dollars it costs to build.

Tips for Writing Circle Proofs? Steps for writing circle proofs - Make a problem - Draw a circle, mark a dot as a center and then, draw a diameter through the central point. You will use a diameter to make one side of the triangle. Then, let two sides join at a vertex somewhere on the circumference. Divide the triangle in to two - Now, you will have to split the triangle into two sides. For this, you will make a radius from the central point to the vertex on the circumference. Double Isosceles Triangles - You will have to identify two sides of each small triangle that are radii. In a specific circle, all of them are the same. It indicates every small triangle have two sides with the same length. It means both triangles are isosceles triangle. Isosceles triangle angle - If every small triangle has two equal angles, it means they are isosceles. Addition of 180 degrees in the angles of the big triangle - The internal angle's sum must be 180 degrees. Three angles a, b and a+b is the part of the big triangles. If we combine 2a + 2b, it will be equal to 180 degree. Therefore, a + b is equal to 90 degree. These worksheets explain how to prove the congruence of two items interior to a circle. Your students will use these worksheets to learn how to perform different calculations for the parts of circles (e.g. secants, chords, angles, circumferences, etc.) using the correct mathematical proofs. Sheets include necessary proofs.

# Print Circle Proofs Worksheets

## Circle Proofs Lesson

This worksheet explains how to prove the congruence of two triangles interior to a circle. A sample problem is solved.

## Practice Problems

Two practice problems are provided that you will work through. Students will do the proofs.

## Circle Proofs Worksheet Problems 1 - 5

Five diagrams are provided and a boat load of answer keys. Students will perform the proofs.

## Worksheet Problems 6 - 10

Page 2 of the previous worksheet set.

## Practice Problems 1 - 5

Ten diagrams are provided. Students will perform the proofs with circles.

## Circle Proofs Practice Problems 6 - 10

Finish off this set strong with page 2.

## Review and Practice Page 1

This worksheet explains how to prove the congruence of two triangles interior to a circle. A sample problem is solved.

## Review and Practice Page 2

The first three of six practice problems are provided. Students will work this skill a little harder.

## Review and Practice Page 3

The second three of six practice problems are provided. We will be working on the same skill we have focused on here from the get go.

## Graphs of Circles Circle of Proofs Quiz Page 1

Students will demonstrate their proficiency in this skill. This page contains the first 5 of 10 problems.

## Quiz Page 2

Students will demonstrate their proficiency with this skill. This page contains the last 5 of 10 problems.

## Skills Check

Students will perform a series of proofs. Three problems are provided, and space is included for students to copy the correct answer when given.