Becca says that she can use elimination to solve the system of equations at the right if she multiplies either of the equations by -1. do you agree with becca? explain. 3x + 2y = -1 3x + 4y = 5

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.