Answer:
20/29
Step-by-step explanation:
sin θ = 21/29
Use Pythagorean identity:
sin² θ + cos² θ = 1
(21/29)² + cos² θ = 1
441/841 + cos² θ = 1
cos² θ = 400/841
cos θ = ±20/29
Since 0° < θ < 90°, cos θ > 0. So cos θ = 20/29.
I have encountered this problem before. The figure gave out 3 chords, 2 of which are diameters, and 1 radius.
A chord is a line segment that joins any two points on a circle.
A diameter is the longest chord on a circle. It originates at one side of the circle, passes through the middle point of the circle, and end on another side of the circle.
The chords in the figure area: AD, BE, and DE. AD and BE are diameters, they pass through F.
Among the choices: A.) AD and B.) BE are the chords.
CF and DF are radii. They only end up in the middle point of the circle.
