Which of the following shows 2 + (x + 3y) rewritten using the Associative Property of Addition? (3 points) 2 + x + 3y
(2 + x) + 3y
2x + (3 + y)
x + (2 + 3y)

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.