In this video, you will learn how to write a logic proof with statements and reasons in order to prove two triangles are congruent.

Start every proof by marking the triangle with the information in the “Given” part of the problem. Write the given information in the “Statements” area. For the “Reasons” section, simply write “Given” since it was given in the problem. You can either write all the given information in separate lines or just in one point.

Since two pairs of corresponding sides are congruent and the corresponding angles between the sides are congruent, the Side-Angle-Side (SAS) Theorem can be used to explain the congruence of the two triangles. Finally, write that the two triangles are congruent in the “Statements” section and the SAS Theorem for the “Reasons” section.

This is a very simple proof; it shows the basics of writing a logical proof for geometry. Remember to always start by marking up the diagram before writing the proof to increase your understanding of congruence.

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