Answer:
x = 2
Explanation:
Given 2 secants drawn from an external point to the circle, then
EC × ED = EB × EA, that is
(x + 4)(x + 4 + 1) = (x + 1)(x + 1 + 11)
(x + 4)(x + 5) = (x + 1)(x + 12) ← expand factors on both sides
x² + 9x + 20 = x² + 13x + 12 ← subtract x² + 13x from both sides
- 4x + 20 = 12 ( subtract 20 from both sides )
- 4x = - 8 ( divide both sides by - 4 )
x = 2