Drawing Triangles www.mathsrevision.com Using a Protractor SAS triangles www.mathsrevision.com ASA triangles SSS triangles 29-Jul-18 Created by Mr. Lafferty

(SAS) Starter Questions Q1. Convert the percentages to fractions. (a) 30% (b) 60% Q2. Write down all the factors of 16. Q3. Calculate the missing angles. 80o Q4. Round the following to 1 decimal place. (a) 4.549 (b) 6.551 29-Jul-18 Created by Mr. Lafferty

A 180o Protractor Outside scale from 0o to 180o going in a clockwise direction. Inside scale from 0o to 180o going in an anti-clockwise direction. 29-Jul-18

You need to be able to measure an angle to the nearest degree You need to be able to measure an angle to the nearest degree. To help you do this you should always: 1. Look directly down onto the cross point. 2. Always use the protractor in a horizontal manner as shown below.  29-Jul-18

Measuring Angles with a 180o Protractor 2 0 on the inside so use inside scale 67o 0 on the outside so use outside scale 29-Jul-18

Measuring Angles with a 180o Protractor 120o 3 Measuring Angles with a 180o Protractor 120o 4 0 on the inside so use inside scale 135o 0 on the outside so use outside scale 29-Jul-18

Drawing SAS Triangles www.mathsrevision.com Learning Intention Success Criteria 1. Understand the steps for drawing SAS triangles. 1 We are learning how to draw SAS triangles. www.mathsrevision.com Be able to draw SAS triangles. 29-Jul-18 Created by Mr. Lafferty Maths Dept.

Drawing SAS Triangles SAS Triangles Side Side Angle 29-Jul-18 Created by Mr. Lafferty

Drawing SAS Triangles Toolkit required Ruler 2. Protractor 3. Pencil & Paper 29-Jul-18 Created by Mr. Lafferty

Drawing SAS Triangles Example : Draw to scale the triangle ABC with AB = 6cm and angle CAB = 30o and AC = 5cm A Step 1 Draw line AB=6cm Step 2 Measure angle CAB from A C X Step 3 Draw the line AC = 5cm through X. Label it C. A B Step 4 Join C to B. Check angles add to 180o 29-Jul-18 Created by Mr. Lafferty

Created by Mr. Lafferty Maths Dept. Drawing SAS Triangles Now try TJ2b Ex 1 Ch5 (page 43) www.mathsrevision.com 29-Jul-18 Created by Mr. Lafferty Maths Dept.

Starter Questions www.mathsrevision.com Q1. Convert to the 24 hour clock. (a) 7:25 pm (b) 6:50 am Q2. Write down lowest common multiple of 3, 4 , 5. Q3. List the first 4 prime numbers. www.mathsrevision.com Q4. Round the following to nearest 1000. (a) 12,501 (b) 369,765 29-Jul-18 Created by Mr. Lafferty

Part 2 : ASA triangles Drawing ASA Triangles 29-Jul-18 Created by Mr. Lafferty

Drawing ASA Triangles www.mathsrevision.com Learning Intention Success Criteria 1. Understand the steps for drawing ASA triangles. 1 We are learning how to draw ASA triangles. www.mathsrevision.com Be able to draw ASA triangles. 29-Jul-18 Created by Mr. Lafferty Maths Dept.

Drawing ASA Triangles ASA Triangles Angle Angle Side 29-Jul-18 Created by Mr. Lafferty

Drawing ASA Triangles Toolkit required Ruler 2. Protractor 3. Pencil & Paper 29-Jul-18 Created by Mr. Lafferty

Drawing ASA Triangles Example : Draw to scale the triangle PQR with PQ = 8cm and angle RPQ = 30o and RQP = 40o P Step 1 Draw line PQ Step 2 Measure Angle RPQ from P R Step 3 Measure angle RQP from Q Q P Step 4 Intersection point is R Check angles add to 180o 29-Jul-18 Created by Mr. Lafferty

Created by Mr. Lafferty Maths Dept. Drawing ASA Triangles Now try TJ2b Ex 2 Ch5 (page 45) www.mathsrevision.com 29-Jul-18 Created by Mr. Lafferty Maths Dept.

Starter Questions www.mathsrevision.com Q1. Convert to the 12 hour clock. (a) 15:45 (b) 05:59 Q2. Write down lowest common multiple of 2, 5. Q3. List the prime numbers between 10 and 20. www.mathsrevision.com Q4. Round the following to nearest 100. (a) 27,942 (b) 99,949 29-Jul-18 Created by Mr. Lafferty

Part 3 : SSS triangles Drawing SSS Triangles 29-Jul-18 Created by Mr. Lafferty

Drawing SSS Triangles www.mathsrevision.com Learning Intention Success Criteria 1. Understand the steps for drawing SSS triangles. 1 We are learning how to draw SSS triangles. www.mathsrevision.com Be able to draw SSS triangles. 29-Jul-18 Created by Mr. Lafferty Maths Dept.

Drawing SSS Triangles SSS Triangles Side Side Side 29-Jul-18 Created by Mr. Lafferty

Drawing SSS Triangles Toolkit required Ruler 2. Compass 3. Pencil & Paper 29-Jul-18 Created by Mr. Lafferty

Drawing SSS Triangles Example : Draw to scale the triangle XYZ with XY = 3cm and XZ = 5cm and YZ = 4cm X y Step 1 Draw line XY=3cm Z Step 2 Use your compass to draw part of a circle centre X radius XZ=5cm Step 3 Use your compass to draw part of a circle centre Y radius YZ=4cm X Y Step 4 Intersection point is labelled Z Step 5 Draw in line XZ and YZ to complete triangle Check angles add to 180o 29-Jul-18 Created by Mr. Lafferty

Now try TJ2b Ex 3 Ch5 (page 47) Drawing SSS Triangles Have you updated your Learning Log ? Drawing SSS Triangles Now try TJ2b Ex 3 Ch5 (page 47) www.mathsrevision.com 29-Jul-18 Created by Mr. Lafferty Maths Dept.