4x2 - 7 + 2x - 3x² + 8x - 6

Having a hard time understanding this question (see attachment).

Which of the following graphs could represent a cubic function?

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.