In Fig. 15.77, ∠AOB=90°, AC=BC, OA=12 cm and OC=6,5 cm. Find the area of Δ AOB.
Since,
The mid-point of the hypotenuse of a right triangle is equidistant from the vertices
Therefore,
CA = CB = OC
CA = CB = 6.5 cm
AB = 13 cm
In right (OAB)
We have,
AB2 = OB2 - OA2
132 = OB2 + 122
OB = 5 cm
Therefore,
Area (Δ AOB) = (OA * OB)
= (12 * 5)
= 30 cm2