**(a) In figure (1) given below, equilateral triangle EBC surmounts square ABCD. Find angle BED represented by x.**

**(b) In figure (2) given below, ABCD is a rectangle and diagonals intersect at O. AC is produced to E. If ∠ECD = 146°, find the angles of the ∆ AOB.**

**(c) In figure (3) given below, ABCD is rhombus and diagonals intersect at O. If ∠OAB : ∠OBA = 3:2, find the angles of the ∆ AOD.**

**Solution:**

**More Solutions:**

- If the diagonal AC bisects A, then prove that:
- Prove that it is a square.
- Show that ABCD is a square.
- Show that PQ is bisected at O.
- Show that AC and PQ bisect each other.
- Prove that AP and DQ are perpendicular to each other.
- Prove that CQ || AP.
- The four bisectors form a quadrilateral ABCD.
- The bisector of ∠A meets DC in E and AB = 2 AD.
- A and B meet at E which lie on DC.