Solve the equation: 7.2-2x=3.8, x=how much.
解方程：7.2-2x=3.8，x=多少．
<gadget id="calculator">7.2 - 3.8</gadget>
<output>3.4</output>

<gadget id="calculator">3.4 / 2</gadget>
<output>1.7</output>

<result>1.7</result>