This isosceles trapezoid
As Most conveniently , it is to prepare a drawing , in line with the conditions of the problem . The angles of 80° adjacent to each other , then it will angles are 100° . The first that comes to mind at the thought figure is the isosceles trapezoid .
1 . We draw a straight line ( figure 1 )
2, Na simple we set two angles of 80° ( figure 2 )
3. Now you must determine the angles 100° notice that 80° + 100° = 180° , so the missing side of the quadrangle must be parallel to the first straight line . We draw a parallel simple and get isosceles trapezoid ( figure 3 )
Immediately drawings lit.f
