4x+5y=13,3x+2y=8 in substitution method

Consider 6x2 + 6x + 1. which term immediately tells you that this expression is not a perfect square trinomial? justify your answer

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.

597008.439431 to the nearest thousand