Tangram Area

Weekly Problem 29 - 2008
The seven pieces in this 12 cm by 12 cm square make a Tangram set. What is the area of the shaded parallelogram?
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Tangram Area


The seven pieces in this $12 \; \text{cm} \times 12 \; \text{cm}$ square make a Tangram set. What is the area of the shaded parallelogram?

If you liked this problem, here is an NRICH task that challenges you to use similar mathematical ideas.