m31541 Classifiying, measuring and constructing angles 1.1 2009/08/22 09:20:02.450 GMT-5 2009/08/22 09:41:02.011 GMT-5 gert bezuidenhout gert bezuidenhout gertb@mweb.co.za gert bezuidenhout gert bezuidenhout gertb@mweb.co.za gert bezuidenhout gert bezuidenhout gertb@mweb.co.za Mathematics and Statistics en

1. How do you construct (draw) any size of angle? To do this, you require the following: compasses, protractor and ruler General: construction of e.g. ABˆC size 12{A { hat {B}}C} {} = 60° Start by drawing a line b) Make a mark on the line c) Place your protractor’s mark in the middle of your mark d) Read from the 0º on the right-hand side to the desired degree

e) Name your angle correctly [e.g. ABˆC size 12{A { hat {B}}C} {} = 60° or Bˆ1 size 12{ { hat {B}} rSub { size 8{1} } } {} = 60° ] 2. How would you go about constructing an angle of, for example, 330º if the protractor can measure only angle sizes up to 180º?Write down your plan below: 3. Construct the following angles and classify each and indicate the limits of degrees. E.g. 60° -- acute angle(classification) --- 0° < x < 90° (limits of°)Limits of ° are read as follows: x greater than 0° and smaller than 90° Angle Sketch Classification(kind of angle) Limits of ° 3.1 PQˆR size 12{P { hat {Q}}R} {} = 75° 3.2 ABˆC size 12{A { hat {B}}C} {} = 125° 3.3 HFˆG size 12{H { hat {F}}G} {} = 325° 3.4 CDˆE size 12{C { hat {D}}E} {} = 180° 3.5 KLˆM size 12{K { hat {L}}M} {} = 90° 3.6 RSˆT size 12{R { hat {S}}T} {} = 360° HOMEWORK ASSIGNMENT 1 There are angles all around you....Determine the size of each of the angles indicated (with the aid of your protractor),write down the size of the angle concernedand classify it.

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2. Construct the following angles by using your ruler and protractor. 2.1 A watch with an angle of 45º between the two numbers. 2.2 A sun bed with an angle of 160° 2.3 A helicopter dropping at an angle of 35º with horizontal. 2.4 A reading lamp with angles 115º and 65º.

CLASSWORK ASSIGNMENT 1 2. 360⁰ – 330⁰ = 30⁰ size 12{ and } {} Construct 30⁰ size 12{ and } {}Acute angle 0⁰∠ size 12{∠} {}Q∠ size 12{∠} {} 90⁰ size 12{ and } {}Obtuse angle 90⁰∠ size 12{∠} {}B∠ size 12{∠} {} 180⁰ size 12{ and } {}Reflexangle 180⁰∠ size 12{∠} {}F∠ size 12{∠} {} 360⁰ size 12{ and } {}Straight (flat) angle D = 180⁰ size 12{ and } {}Right angle L = 90⁰ Angle of rotation S = 360⁰

Acute ∠ size 12{∠} {} Obtuse ∠ size 12{∠} {} Obtuse ∠ size 12{∠} {} 1.4 Reflex ∠ size 12{∠} {} Obtuse ∠ size 12{∠} {} Acute ∠ size 12{∠} {} Acute ∠ size 12{∠} {} Acute ∠ size 12{∠} {} Acute ∠ size 12{∠} {} Acute ∠ size 12{∠} {} Acute ∠ size 12{∠} {} Reflex ∠ size 12{∠} {} Acute ∠ size 12{∠} {} Obtuse ∠ size 12{∠} {} Obtuse ∠ size 12{∠} {} and Acute ∠ size 12{∠} {} Obtuse ∠ size 12{∠} {} and Acute ∠ size 12{∠} {} CLASSWORK ASSIGNMENT 2 1.a) Acute angle b) one right angle c) one obtuse angle acute-angled right-angled / acute-angled obtuse-angled right-angled