Question

I need to know the answer no explanation needed i have an explanation paper

Answer 1

The triangle ACD is a right angle, since it is a triangle in a semicircle.

Application of pythagoras theorem:

The theorem states that the square of the hypotenuse is equal to the square of the other two sides; hence:

`CD^2=AC^2+AD^2`

solving for CD:

`CD=√(9^2+4^4)=9.8`

ANSWER

CD = 9.8