Help me? Pls

Multiply. write your answer in simplest form. 3/8 x 5/7

What are the solution(s) to the quadratic equation x2 – 25 = 0? o x = 5 and x = -5ox=25 and x = -25o x = 125 and x = -125o no real solution

The distance of a chord from the centre of a circle is 12cm and the lenght of the chord is 10cm. find the radius of the circle