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.

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..