What is the area of the shaded region of a rectangle inscribed in a circle?

Abag contains 4 red, 7 blue and 5 yellow marbles. event a is defined as drawing a yellow marble on the first draw and event b is defined as drawing a blue marble on the second draw. if two marbles are drawn from the bag, one after the other and not replaced, what is p(b|a) expressed in simplest form? a. 7/16 b. 7/15 c. 14/16 d. 14/15

See attachment below and find the equivalent of tan(∠qsr)

What is the value of x? enter your answer in the box.