All the angles of the quadrilateral can be determined.
You will easily be able to determine that the diagonals intersect at right angles.
∠SWH and ∠SIH are measured by the arc of 80º
Then ∠WHI and ∠WSI are measured by the arc of 100º
Those angles give you the information necessary to determine that the diagonals are perpendicular.
The acute angles in the other 2 right triangles will satisfy 4 simultaneous linear equations in 4 unknowns.
Remember that the opposite angles in a cyclic quadrilateral ae supplementary!
7/6/22 9:53 PM and
My answer is only partially correct.
The four angles measured by the given arcs, obviously can be determined; this shows that the diagonals are perpendicular.
The angles in the other 2 right triangles can be determined...but not in any simple fashion.