Question 18
In rhombus $ABCD$, the circle through $A,B,C$ has radius 6, while the circle through $A,B,D$ has radius 2. Compute the area of $ABCD$.
Answer entry: use a reduced fraction a/b or a decimal with a dot. The checker recognizes only explicitly listed exact forms; it does not guarantee recognition of all algebraically equivalent forms. An unrecognized equivalent form requires manual checking and must not be treated as wrong or scored zero solely because it is unrecognized.
Answer entry: use a reduced fraction a/b or a decimal with a dot. The checker recognizes only explicitly listed exact forms; it does not guarantee recognition of all algebraically equivalent forms. An unrecognized equivalent form requires manual checking and must not be treated as wrong or scored zero solely because it is unrecognized.