are being used to get the equation in step 6.
are being used to get the equation in step 8.
By a similar argument used to prove that △AEB ≅ △CED, we can show that △ ≅ △CEB by. So, ∠CAD ≅ ∠ by CPCTC. Therefore, AD || BC by the converse of the theorem. Since both pair of opposite sides are parallel, quadrilateral ABCD is a parallelogram.
In step 14, "similar argument" means to draw segment and follow the same logic in steps 3-12.
Did you find these answers helpful?
Special Parallelograms
Instruction