If X+3=8, Y-4=9, then XY=how much.
如果X+3=8，Y-4=9，那么XY=多少．
<gadget id="calculator">8 - 3</gadget>
<output>5</output>

<gadget id="calculator">9 + 4</gadget>
<output>13</output>

<gadget id="calculator">5 * 13</gadget>
<output>65</output>

<result>65</result>