The second angle of a triangle is 30 degrees larger than the first, while the third angle of the triangle is twice as large as the second. How big is the first angle? (Remember that the
sum of the angles in any triangle is 180 degrees.)

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.