问题
问答题
The figure above shows the dimensions ofa rectangular board that is to be cut into four identical pieces by making cuts at points A, B, and C, as indicated. If x=45, what is the length of AB ？(1 foot=12 inches)
答案
参考答案：
5英尺3英寸
解析：
如图所示做辅助线，其中EF⊥AB。根据长方形的性质可知EF=AE=6英寸=0.5英尺，[*]=10英尺，BE=BC，所以有：
AC=AE+EB+BC=2BE+AE
=10英尺
→BE=BC=4.75英尺
→AB=AE+BE=4.75+0.5
=5.25英尺=5英尺3英寸