What is the point on the unit circle for the angle below?

If given an equation of a line such as -1/2x+6 how would you create an equation of a line parallel and perpendicula to this line that goes through another point such as (4,10)

What is the sum of the first 8 terms of the geometric series

Aquadrilateral has exactly 3 congruent sides davis claims that the figure must be a rectangle why is his claim incorrect.