The diagonals of a parallelogram ABCD intersect at O. A line through O intersects AB at X and DC at Y. Prove that OX = OY. [4 MARKS]
Diagram : 1 Mark
Concept : 1 Mark
Proof : 2 Marks
Consider ΔAXO and ΔCYO.
AO=CO [Diagonals bisect each other]
∠AOX=∠COY [Vertically opposite angles]
∠AXO=∠CYO [Alternate angles]
∴ΔAXO≅ΔCYO. [AAS congruency]
OX=OY [CPCT]