急!在线等答案!用英语回答的数学题.
问题描述：
急!在线等答案!用英语回答的数学题.
Use a ruler and a protractor to draw 3 lines AB,BC and CD such that BC ⊥ AB and BC ⊥ CD.Are AB and CD parallel to each other?Explain your answer briefly.
答
Yes,if the three lines are in a surface,AB and CD parallel to each other.Because BC ⊥ AB,BC ⊥ CD,so it is a rectangle,so AB and CD parallel to each other.If the three lines are not in a surface,AB a...