Through the height of an equilateral tetrahedron a, we construct a plane that intersects the lateral faces along three lines creating with the base plane of the tetrahedron with angles x, y, z. Prove: tan²x + tan²y + tan²z = 12

The swimming pool is open when the high temperature is higher than 20∘c. lainey tried to swim on monday and thursday (which was 3 days later). the pool was open on monday, but it was closed on thursday. the high temperature was 30∘c on monday, but decreased at a constant rate in the next 3 days. write an inequality to determine the rate of temperature decrease in degrees celsius per day, d, from monday to thursday.

Abag of jelly beans contain 13 pink, green, 20 yellow, 10 black, 7 red, and 11 orange jelly beans. approximately what percent of the jelly beans are pink and yellow?

What is the radius of a circle with an area of 78.5 cubic inches? use 3.14 for pie