Answer; 384cm²

Step-by-step explanation:

A = 384cm²

a Side - 20cm

p Diagonal - 24cm

Using the formulas

A=pq

____

2

________

a= _/p²+ q²

______

2

solving for A

A=1 _________

___ p _/ 4a²-p² = 1 ________

2 ___ . 24 _/4.20² - 24²

2

=384cm²

________

__________

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