What is the equation in standard form of an ellipse centered at the origin and vertex (1,0) and focus (4,0)?

Kapil needed to buy a long wooden beam. he went to two sawmills that each charge an initial fee plus an additional fee for each meter of wood. the following equation gives the price (in dollars) of a wooden beam from the first sawmill as a function of its length (in meters). p = 5+20xp=5+20x

The function models the number of accidents

If value of cos330° is √3/2 then find tan165°.