As shown in a figure, there is a point A on the straight line ① and the straight line ② is drawn from point A.
Line ② is drawn as the angle with line ① to be 10 degrees.
Next, the point B is set on the straight line ② and the straight line ③ is drawn from point B.
Line ③ is drawn as the angle with line ② to be 20 degrees.
In the same way, the straight line ④ is drawn increasing 10 degrees of angles at a time.
Moreover, the point on a straight line and its straight line is set like the point D on line ④.
When this operation was continued several times, the straight line drawn newly overlapped with the straight line ①.
There was no line that is parallel to the straight line ① in the continuous operation.
Answer the following questions.
(1) Find the number of the straight line drawn.
The last straight line which has overlapped with the straight line ① is not counted.
(2) There are some straight lines which are in a vertical position each other.
Answer all numbers of pairs of lines.
(3) There are some straight lines which are in a parallel position each other.
Answer all numbers of pairs of lines.
Line ② is drawn as the angle with line ① to be 10 degrees.
Next, the point B is set on the straight line ② and the straight line ③ is drawn from point B.
Line ③ is drawn as the angle with line ② to be 20 degrees.
In the same way, the straight line ④ is drawn increasing 10 degrees of angles at a time.
Moreover, the point on a straight line and its straight line is set like the point D on line ④.
When this operation was continued several times, the straight line drawn newly overlapped with the straight line ①.
There was no line that is parallel to the straight line ① in the continuous operation.
Answer the following questions.
(1) Find the number of the straight line drawn.
The last straight line which has overlapped with the straight line ① is not counted.
(2) There are some straight lines which are in a vertical position each other.
Answer all numbers of pairs of lines.
(3) There are some straight lines which are in a parallel position each other.
Answer all numbers of pairs of lines.
Answer
(1) Eight lines
(2) ② and ⑤、② and ⑧、④ and ⑥
(3) ③ and ⑦、⑤ and ⑧
(2) ② and ⑤、② and ⑧、④ and ⑥
(3) ③ and ⑦、⑤ and ⑧
Reference
(2)
(3)
