How do you solve for a one veritable equation ??help please

In two or more complete sentences, determine the appropriate model for the given data and explain how you made your decision. (1,-1), (2,0.5), (5,1.5), (8,2)

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.

Based on the diagrams, what is the value of x?