In Fig. 4.72, . If OA = 3x – 19, OB = x – 4, OC = x – 3 and OD = 4, find x.
AO/OC=BO/OD
3X-19/X-3=X-4/4
(x-3)(x-4)=4(3x-19)
X2 -4x-3x+12=12x-76
X2 -7x+12-12x+76=0
X2 -19x+88=0
X2 -11x-8x+88=0
X(x-11)-8(x-11)=0
(x-11)(x-8)=0
x-11=0
x=11
or x-8=0
x=8
x=11 or 8