4X-12=7.2, what is the solution of the equation.
4X-12=7.2，方程的解是多少．
<gadget id="calculator">7.2 + 12</gadget>
<output>19.2</output>

<gadget id="calculator">19.2 / 4</gadget>
<output>4.8</output>

<result>4.8</result>