Solve the equation: (4/5)-2x=(1/4).
解方程：(4/5)-2x=(1/4)．
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(4/5) - (1/4)</gadget>
<output>11/20 = around 0.55</output>

<gadget id="calculator">(11/20) / 2</gadget>
<output>11/40 = around 0.275</output>

<result>11/40 = around 0.275</result>