A brand of small dining table desktop is a rectangle with a length of 60cm and a width of 40cm. Xiao Min wants to design a tablecloth, and its area is the desktop area.
The length of this tablecloth is 60+2xcm and the width is 40+2xcm.
﹙60+2X﹚﹙40+2X﹚=60×40×2
2400+ 120X+80X+4X？ =4800
x？ +50X-600=0
﹙X- 10﹚﹙X+60﹚=0
X = 10 (cm)