Abasketball player shoots a free throw in a game. the quadratic expression models the height of the ball, in feet, where t is the time, in seconds. -15x^2+25t+7

The pyraminx is a rubik's cube-type toy in the shape of a tetrahedron. the pyraminx shown below has edges 15\,\text{cm}15cm long and vertical height h=12.2\,\text{cm}h=12.2cm. the triangle drawn with dashed lines is a right triangle. what is the distance rr? round your answer to the nearest tenth.