If the width of a rectangle is increased by 15 cm, a square will be formed, and the area will increase by 1275 cm. What is the width of the original rectangle in cm?
一个长方形，如果把宽增加15厘米，就形成一个正方形，面积就增加1275厘米，求原来长方形的宽是多少厘米？
<gadget id="calculator">1_275 / 15</gadget>
<output>85</output>

<gadget id="calculator">85 - 15</gadget>
<output>70</output>

<result>70</result>