The area of a trapezoidal vegetable field is 122.55 square meters, the length of the upper base is 18.6 meters, and the length of the lower base is 7.2 meters. How many meters is the height? (solution by equation)
一块梯形菜地面积是122.55平方米，上底长18.6米，下底长7.2米，高是多少米？(用方程解)
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">18.6 * (1/2)</gadget>
<output>9.3</output>

<gadget id="calculator">7.2 * (1/2)</gadget>
<output>3.6</output>

<gadget id="calculator">9.3 + 3.6</gadget>
<output>12.9</output>

<gadget id="calculator">122.55 / 12.9</gadget>
<output>9.5</output>

<result>9.5</result>