Tech Math 2

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Tech Math 2

• Day 3 Right, Obtuse, and Acute Angles

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Warm-up

• Directions Find the missing angles below.

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3
4
2
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Assignment Answers Vertical Angles W.S. 2-4

• 2. Yes No
• 3. a. ltDCE 150, ltBCE 30
• b. ltBCE 35 , ltDCE 145
• 4. a. X 10, ltRTSltUTV 36
• b. ltRTU 57, ltUTV 123
• c. x 23, ltRTU 127, ltRTS 53

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Objective

• Students will be able to
• Define right, obtuse, and acute angles
• Define the supplementary and complementary angle
  theorems
• Identify and distinguish between obtuse, acute,
  and right angles
• Find angle measures directly or using algebraic
  expressions
• Find the measure of a complement or supplement
  angle

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Right Angles

• Definition An angle measuring 90 degrees.

Means perpendicular/90 degrees
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Complementary Angles

• Definition two angles whose measure total 90
  degrees.

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Obtuse Angle

• An angle measuring more than 90 but less than
  180

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Acute Angle

• An angle measuring more than 0 but less than 90

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Straight Angle

• An angle measuring 180

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Supplementary Angles

• Two angles whose measures total 180

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Right, Obtuse, Acute, Straight?
Acute
Obtuse
Right
Straight
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Examples

• ltABC 30 , find ltCBD
• ltABD 90
• ltCBD 90 30 60

Ex. 1
A
C
D
B
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Examples

• ltABC x,
• ltCBD 4x - 5
• Find x, ltABC and ltCBD
• X4x-5 90
• 5x-590
• 5 5
• 5x 95
• 5 5
• X 19
• ltABC x 19
• ltCBD 4(19)-571

Ex. 2
A
C
D
B
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Examples

• ltABC x,
• ltCBD x
• Find x, ltABC and ltCBD
• XX 90
• 2x90
• 2 2
• x 45
• ltCBD 45
• ltABD 45

Ex. 3 S.P.
A
C
D
B
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Examples

• ltABC 3x-6
• 0lt3x-6lt90
• 6 6 6
• 6lt3xlt96
• 3 3 3
• 2ltxlt32

Ex. 4 Find the range of x that would make ltABC
acute.
A
C
B
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Examples

• ltABC 2x30
• 90lt2x30lt180
• -30 -30 -30
• 60lt2xlt150
• 2 2 2
• 30ltxlt75

Ex. 5 S.P. Find the range of x that would make
ltABC obtuse.
A
B
C
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Questions?
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Work Time
Assignment Right, Obtuse, and Acute Angle W.S.
Angle Identity W.S.