Answer:
x = 4
Step-by-step explanation:
When a tangent and a secant are drawn from an external point to a circle.
Then the product of the external part of the secant and the entire secant and the square of the measure of the tangent are equal, hence
x(x + 5) = 6²
x² + 5x = 36 ( subtract 36 from both sides )
x² + 5x - 36 = 0 ← in standard form
(x + 9)(x - 4) = 0 ← in factored form
Equate each factor to zero and solve for x
x + 9 = 0 ⇒ x = - 9
x - 4 = 0 ⇒ x = 4
However, x > 0 ⇒ x = 4