Answer:
278 square centimeters
Explanation:
You need to use the Pythagorean Theorm. If you're pyramid is a perfect square, then to the middle the length is 5. Because 10/2 is 5. You then use the Pythagorean Theorm (a^2 + b^2 =c^2) to find the side length of the traingle. When you square the hypotenuse and subtract the bottom leg sqaured, you are left with 3.46274054 after square rooting it. (c^2-a^2=b^2) Plug these into the equation for a right, rectangluar pyramid. You then get 277.9, rounded, is 278.
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