Draw two straight lines on a rectangle with an area of 150 square centimeters, divide the rectangle into a square, a right triangle, and a right trapezoid, so that the area ratio of the square, triangle, and trapezoid is 1:2:3. What is the length of the long side of this right triangle in centimeters?
在面积150平方厘米的长方形上画两条直线，把这个长方形分成一个正方形、一个直角三角形、和一个直角梯形，使正方形、三角形、梯形面积之比为1：2：3．这个直角三角形的长直角边等于多少厘米．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">50 * (2/5)</gadget>
<output>20</output>

<result>20</result>