won’t multiply π out in
circle problems. Because
the answer choices will
usually be in terms of π
(6π instead of 18.849...),
you can save yourself
some trouble by leaving
your work in terms of π.- The area of a circle is πr2, where r is the radius of the circle.
area = π4^2 = 16π- A tangent is a line that touches a circle at exactly one point. A radius drawn from that
tangent point forms a 90-degree angle.
Circles Have Names?
If a question refers to
Circle R, it means that the
center of the circle
is point R.Let’s see how these rules can show up on the SAT.