天山 7-11

lololo

Q11: Note: Not drawn to scale. A rectangular picture is surrounded by a boarder, as shown in the figure above. Without the boarder the length of the picture is twice its width. If the area of the boarder is 196 square inches, what is the length, in inches, of the picture, excluding the boarder? A. 10 B. 15 C. 30 D. 40 E. 60

Please give me a help!! thanks!!

mikejia

边界的面积是196

设长方形长边为x,短边为x/2. 则196=2*(2x)+2*(2*x/2)+4*4 =>x=30

lololo

谢谢，我也是这么算的，不小心算错了

[em04]