What is the surface area of a regular square pyramid with a slant height of 12 cm and a lateral edge of 13 cm?

\(\text{Base length}=2\times\sqrt{13^3-12^2}\\ \;\;\qquad\qquad\;\;=2\times 5 \\\;\;\qquad\qquad\;\;= 10\)

\(\text{Surface area}=\text{Base length}^2+2\times \text{Base length}\times \text{Slant height}\\\qquad\qquad\quad\;=10^2+2\times 10 \times 12\\\qquad\qquad\quad\;=340 \text{cm}^2\)

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