If 4(x-1.3)=2.8, then x**2=how much.
如果4(x-1.3)=2.8，那么x**2=多少．
<gadget id="calculator">4 * 1.3</gadget>
<output>5.2</output>

<gadget id="calculator">5.2 + 2.8</gadget>
<output>8</output>

<gadget id="calculator">8 / 4</gadget>
<output>2</output>

<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<result>4</result>