The perimeter of a rectangle is equal to that of a square. The ratio of the length to width of the rectangle is 7:3. The area of the square is 8 square meters more than the area of the rectangle. Find the area of the square.
一个长方形与一个正方形的周长相等，长方形的长与宽的比是7：3，正方形的面积比长方形的面积多8平方米，求正方形的面积．
<gadget id="calculator">25 * 2</gadget>
<output>50</output>

<result>50</result>