we know that if points a and b lie on the circle and O is the center so OA is the radius OA=OB 5x-11=4(x-1)-----> 5x-11=4x-4----> 5x-4x=11-4-----> x=7 OA=5x-11-------> OA=5*7-11-----> OA=24 units
the diameter is (OA+OB) 2*OA------> 2*24------> 48 units
