When x=5, what is the value of 2x-1.7*4.
当x=5时，2x-1.7*4的值是多少．
<gadget id="calculator">2 * 5</gadget>
<output>10</output>

<gadget id="calculator">1.7 * 4</gadget>
<output>6.8</output>

<gadget id="calculator">10 - 6.8</gadget>
<output>3.2</output>

<result>3.2</result>