__÷__×+ =30 how do u fill in the blank for this problem

What is the approximate value of  x  in the equation below.–3.396–0.7080.3040.955

I'm marking the brainliest and it's 15 points

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.