4x-5*6=12, 8x-3x=15.6, 7.2*0.5-3x=1.2.
4x-5*6=12,8x-3x=15.6,7.2*0.5-3x=1.2．
<gadget id="calculator">3.6 - 1.2</gadget>
<output>2.4</output>

<gadget id="calculator">2.4 / 3</gadget>
<output>0.8</output>

<result>0.8</result>