Step-by-step explanation:
know, ∠BGA = 90
In right angled triangle BGA
AB = 12 cm (diameter of circle)
⇒ (AB)2 = (AG)2 + (BG)2
⇒ 122 = 82 + (BG)2
⇒ BG = 4√5
In right angled triangle BCG
Let CG be x cm.
⇒ (BC)2 = (CG)2 + (BG)2
⇒ (BC)2 = x2 + (4√5)2 ----(1)
As we know,
⇒ (BC)2 = CG × CA ----(2)
From equation (1) and equation (2)
⇒ x2 + (4√5)2 = x × (x + 8)
⇒ x2 + (4√5)2 = x2 + 8x
⇒ 8x = 80
⇒ x = 10 cm
From equation (2)
⇒ (BC)2 = CG × CA
⇒ (BC)2 = 10 × 18 = 180
⇒ BC = √180 = 6√5
