Line segment. Distance between two points.

Line. Opposite directions infinitely.

Ray. Goes in one direction infinitely.

Point. A location.

Angle. Two rays that share a common vertex.

Vertex. The corner of an angle or shape.

Legs. Another way to say the sides or rays of an angle.

WHAT YOU SHOULD ALREADY

KNOW.

COPY IN SPIRAL.2 WAYS TO NAME AN ANGLE

:

1. BY LEG, VERTEX, LEG

VERTEX LETTER MUST BE IN THE MIDDLE.

QRS SRQ

R

Q

SR

2. BY VERTEX ONLY.

ONLY THE VERTEX LETTER.

R

Things you need to know:COPY IN YOUR SPIRAL.

• A circle has 360°

• Straight angle: 180° • Obtuse angle: 91° to 179°• Right angle: exactly 90°• Acute angle: 1°-89°• Supplementary angles: 2 or more angles that add to 180°

ADJACENT Supplementary angles: 2 or more angles that add to 180° and share a common vertex and side.

• Complementary angles: 2 or more angles that add to 90°ADJACENTcomplementary angles: 2 or more angles that add to

90° and share a common vertex and side..

EXAMPLES:Complementary Angles:

Two or more angles whose sum is 90

223236

22 + 36 + 32 =

These angles are complementary

ADJACENT Complementary Angles

• Two or more angles that share a common vertex and side -whose sum is 90

A

B

C

DE

AEB + BEC + DEC

30° 30° 30°

= 90°

EXAMPLESSupplementary Angles

• Two or more angles whose sum is 180

90

33

57

These 3 angles are supplementary

90 + 33 + 57 = 180

ADJACENT supplementary angles

• Two or more angles that share a common vertex and side whose sum is 180

A B

C

D

E

F

47 61

23 AFB + BFC + CFD + DFE =What is the measure

of CFD?

Triangle angles are supplementary.

ALWAYS.

Because all 3 angles will ALWAYS add to 180°.

COPY IN SPIRAL:

NOW YOU MAY CLOSE YOUR SPIRALAND WORK ON THE PRACTICE WORKSHEET..