Trapezoid Properties - Problem 2 2,814 views
Using what know about isosceles trapezoids, which are identified by looking at congruent bases when we have another pair of bases that are parallel, we can use the fact that same side interior angles are always going to be supplementary.
So x here plus 60 must be 180 which means x is 120 degrees. Y we know is going to be congruent to 60 degrees. So I’m going to say that y is 60 degrees.
Again the key thing here is remembering that your base angles are going to be congruent to each other and that these two same side interior angles will be supplementary.