Answer:
see below
Step-by-step explanation:
1. Semi-circles have an arc/angle measure of 180°.
2. The angle where chords cross is the average of the subtended arcs. Linear angles are supplementary.
3. It is a good idea to be familiar with algebraic manipulation of quadratic equations, including eliminating parentheses and putting in "general form" (answer B). It is also useful to be familiar with squares of integers less than 20.
4. You have run across this before in your other questions. Opposite angles of an inscribed quadrilateral are supplementary. (The opposite arcs are double the angle measures, so sum to 360°.)
5. After the fashion of question 3, fill in the parameters in the circle equation.
