The base and area of a triangle are equal to the base and area of a parallelogram respectively. The height of the parallelogram is 10 cm. What is the height of the triangle in cm?
一个三角形的底和面积与一个平行四边形的底和面积分别相等，平行四边形的高是10cm，三角形的高是多少cm
<gadget id="calculator">10 * 2</gadget>
<output>20</output>

<result>20</result>