It is known that 4x+3=15, then 5x-3=how much.
已知4x+3=15，那么5x-3=多少．
<gadget id="calculator">15 - 3</gadget>
<output>12</output>

<gadget id="calculator">12 / 4</gadget>
<output>3</output>

<gadget id="calculator">5 * 3</gadget>
<output>15</output>

<result>12</result>