6.5. Parallelogram Classification http://www.ck12.org
Example B
Is a rhombus SOMETIMES, ALWAYS, or NEVER a square? Explain your reasoning.
A rhombus has four congruent sides, while a square has four congruent sides and angles. Therefore, a rhombus is
only a square when it also has congruent angles. So, a rhombus is SOMETIMES a square.
Example C
List everything you know about the squareSQRE.
A square has all the properties of a parallelogram, rectangle and rhombus.
TABLE6.7:
Properties of Parallelograms Properties of Rhombuses Properties of Rectangles• SQ||ER •SQ∼=ER∼=SE∼=QR •^6 SER∼=^6 SQR∼=^6 QSE ∼=
(^6) QRE
• SE||QR •SR⊥QE •SR∼=QE
• SQ∼=ER •^6 SEQ∼=^6 QER∼=^6 SQE ∼=
(^6) EQR
• SA∼=AR∼=QA∼=AE
• SE∼=QR •^6 QSR ∼=^6 RSE ∼=^6 QRS ∼=
(^6) SRE
• SA∼=AR
• QA∼=AE
•^6 SER∼=^6 SQR
•^6 QSE∼=^6 QRE
Watch this video for help with the Examples above.