Answer:
x = 6
Step-by-step explanation:
<em>If </em><em>two secants</em><em> are drawn from</em><em> a point outside </em><em>the circle, then the </em><em>product</em><em> of the lengths of</em><em> one secant </em><em>and its</em><em> external segment</em><em> equals the </em><em>product </em><em>of the lengths of</em><em> the other secant </em><em>and its</em><em> external segment</em><em> </em>
Let us solve the question.
∵ There is a circle in the given figure
∵ There are two secants intersected at a point outside the circle
∵ The length of one of them = 8
∵ The length of its external segment = x
∵ The length of the other secant = 4 + 8 = 12
∵ The length of its external segment = 4
→ By using the rule above
∴ 8 × x = 12 × 4
∴ 8x = 48
→ Divide both sides by 8
∴ x = 6
. So answer 
.