Lucia is an archaeologist trekking through the jungle of the Yucatan Peninsula. She stumbles upon a stone structure covered with creeper vines and ferns. She immediately begins taking measurements of her discovery. (Hint: Drawing some figures may help.)

7. Around the perimeter of the building, Lucia finds small alcoves at regular intervals carved into the stone. The alcoves are triangular in shape with a horizontal base and two sloped equal-length sides that meet at a right angle. Each of the sloped sides measures 141 inches. Lucia has also found several stone tablets inscribed with characters. The stone tablets measure 221 inches long. Lucia hypothesizes that the alcoves once held the stone tablets. Tell whether Lucia's hypothesis may be correct. Explain your answer ​