1. Angles IN and OUT of a Circle
On the next 11 slides, copy ALL the information, including the diagrams

2. CENTRAL ANGLE
Define Central Angle: An angle whose vertex is AT the CENTER.
Central Angle Formula = the intercepted arc
Ex: m<AOC = m AC

3. INSCRIBED ANGLE
Define Inscribed Angle: An angle formed by 2 chords, whose vertex is
ON the circle.
Inscribed Angle Formula = ½ (intercepted arc)
Ex: m<ABC = ½ (mAC)

4. Inscribed Angle Intercepting a Semi-Circle
If an inscribed angle intercepts a semi-circle(which measures 180 degrees), then its measure is half the measure of a semi-circle (which = 90 degrees)
Inscribed Angle Intercepting a Semi-Circle = ½(180)
= 90 degrees
m<ABC = ½ (mAC)

5. Theorem involving 2 inscribed angles that intercept the same arc
When 2 inscribed angles intercept the same arc, the 2 inscribed angles are = and the arc being intercepted is double the inscribed angle.
m<A = m<B because they both intercept arc PQ
m<P = m<Q because they both intercept arc AB

6. Angle formed by a Tangent and a Chord
An angle formed by a tangent(a line that intersects a circle at 1 point) and a chord(a line segment inside a circle that intersects the circle at 2 points) is equal to half the arc(s) it intercepts.
m<CDA = ½ (mCED)
m<CDB = ½ (mCD)

7. Angle formed by 2 Secants
Define an angle formed by 2 secants: the angle formed by 2 secants is half the difference of the 2 arcs being intercepted.
An angle formed by 2 secants = ½ (larger arc – smaller arc)
m<A = ½ (mPS – mNK)

8. Angle formed by a Tangent and a Secant
Define an angle formed by a Tangent and a Secant: the angle formed by a tangent and a secant is equal to half the difference of the 2 arcs being intercepted.
An angle formed by a tangent and a secant = ½ (larger arc – smaller arc)
m<P = ½ (mAC – mBC)

9. Angle formed by 2 Tangents
Define and angle formed by 2 tangents: An angle formed by 2 tangents is equal to half the difference of the 2 intercepted arcs.
m<B = ½ (larger arc – smaller arc)
m<B = ½ (mADC – mAC)

10. Angle formed by 2 Intersecting Chords
Define an angle formed by two intersecting chords: An angle formed by 2 intersecting chords is equal to half the sum of the 2 arcs being intercepted.
An angle formed by 2 intersecting chords = ½ (arc + arc)
m<SVR = ½ (mSR + mTQ)
m<TVQ = ½ (mSR + mTQ)
AND
m<SVT = ½ (mST + mRQ)
m<RVQ = ½ (mST + mRQ)

11. Theorem involving 2 Parallel Chords
When you are given 2 parallel chords, mAB = mCD
If BC II AD, then mAB = mCD