If X+2=12, 12-Y=5, then XY=how much.
如果X+2=12，12-Y=5，那么XY=多少．
<gadget id="calculator">12 - 2</gadget>
<output>10</output>

<gadget id="calculator">10 * 7</gadget>
<output>70</output>

<result>70</result>