It is known that 4x+8=20, then 2x+8=how much.
已知4x+8=20，那么2x+8=多少．
<gadget id="calculator">20 - 8</gadget>
<output>12</output>

<gadget id="calculator">12 / 4</gadget>
<output>3</output>

<gadget id="calculator">2 * 3</gadget>
<output>6</output>

<gadget id="calculator">6 + 8</gadget>
<output>14</output>

<result>14</result>