Question

Please help me with my homework!

Answer 1

2sqrt(5)

Explanation:

Using tangent-secant theorem:

(8+2) × 2 = CD²

20 = CD²

CD = sqrt(20) = 2sqrt(5)

sqrt: square root

Answer 2

2 sqrt(5) = DC

Explanation:

(whole secant) x (external part) = (tangent)^2

the whole secant = 4+4+2 = 10

The external part is 2

We are looking for the tangent

10 * 2 = DC ^2

20 = DC ^2

Take the square root of each side

sqrt(20 ) = DC

sqrt( 4*5) = DC

2 sqrt(5) = DC