A watchtower, built to help prevent forest fires,
was designed as an
isosceles triangle. If the
side of the tower meets
the ground at a 105° angle,
what is the measure of the
angle at the top of the
tower?

In trapezoid efgh, m∠hef=(4x2+16)∘ and m∠gfe=(5x2+12)∘. find the value of x so that efgh is isosceles.

Simplify using positive exponents only.

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.