Chord Properties

A chord is any line in a circle

• True

• False

If $\overline{BD}\cong\overline{DC}$ and  $\overline{EF}\ \perp\ \overline{BC}$ , what conclusions can say about  $\overline{EF}$  ? 
(Hint: Use Chord Theorem #2)

•  $\overline{EF}$  is the radius of circle A

•  $\overline{EF}$  is a secant line of circle A

•  $\overline{EF}$  is the diameter of circle A

•  $\overline{EF}$  is the tangent line of circle A

What do we call the red line?

• Chord
• Arc
• Diameter
• Segment

when you bisect a chord you...

• break it into sections

• you fold it

• you divide it into 2 equal sections

• you copy it/repeat it in another area of the circle

solve for f

• 7

• 14

• 21

• not enough information to solve

solve for the missing angle

• 45 degrees

• 90 degrees

• 100 degrees

• not enough information to answer

solve for the missing angles

• x = 25 y = 45

• x = 45 y = 25

• x = 110 y= 110

• x = 35 y =35

what skill would you use to solve for x

• all triangles have 180 degrees

• use pythagorean theory

• divide the diameter in half

• it is the same as the radius

what skill would you use to solve for x

• pythagorean theory

• bisect the chord

• all triangles have 180 degrees

• find the area of the circle