Explain why you need to prove 2 triangles congruent before you can prove the parts of the triangles congruent.
You need to prove two triangles congruent before you can prove the parts of the triangles congruent because the congruence of the entire triangles guarantees that the corresponding parts of the triangles will also be congruent.
In a triangle, there are several corresponding parts, including angles and sides. When you prove that two triangles are congruent, you establish that all corresponding parts between them are equal in size, shape, and length.
By showing that the entire triangles are congruent, you ensure that all corresponding parts are also congruent. This means that if two triangles are congruent, their corresponding angles will have the same measures, and their corresponding sides will have the same lengths.
Proving the congruence of the entire triangles is crucial because it serves as the foundation for proving the individual parts of the triangles congruent. If you were to skip this step and directly prove the parts of the triangles congruent without proving the triangles congruent, you would not have a solid mathematical basis for your claims.