问题1：构造以下四边形。
(i)四边形DEAR
DE = 4厘米
EA = 5厘米
AR = 4.5厘米
∠E= 60°
∠A= 90°
解决方案：
Steps of construction:
Step 1: Draw a line segment DE of 4 cm.
Step 2: Construct an angle of 60° at E.
Step 3: From E draw an arc of 5 cm and intersect the arc with the angle line, mark the intersection point as A.
Step 4: Draw a 90° angle at A.
Step 5: Draw an arc of 4.5 cm from A and cut the angle line at R.
Step 6: Join DR.
因此，我们具有所需的四边形DEAR。
(ii)四边形TRUE
TR = 3.5厘米
RU = 3厘米
UE = 4厘米
∠R= 75°
∠U= 120°
解决方案：
Steps of construction:
Step 1: Draw a line TR of 3.5 cm.
Step 2: From R construct an angle of 75°.
Step 3: Draw an arc of 3 cm from R and cut the angle line at U.
Step 4: From U construct an angle of 120
Step 5: Draw an arc of 4 cm from U and cut the angle line at E.
Step 6: Join TE.
因此，我们具有所需的四边形TRUE。