Suppose ABCD is a square. Let E be interior to the square such that EDC = ECD = 15°. What is the measure of angle EBC?

A copy of square ABCD is rotated clockwise about vertex A to square A’B’C’D’ such that D’B’C is a straight line segment, as shown below. What is the measure of angle D’ED?

ABCD is a square and point P inside the square is such that PCD is an equilateral triangle. Find the angle α

ABCD is a square of side length 1.

If EFGH are the points on its boundary such that AE=EB, 2BF=FC, 3CG=GD & 4DH=HA then what is the area of the quadrilateral EFGH?