Grade 6 Geometry Unit Re-cap Given two of the three angles in a triangle, how could we find the third angle? Given SAS how could we construct a triangle? Do you think we could construct a triangle give side side side (SSS)? Do you think we could construct a triangle given angle side angle (ASA)? Constructing Triangles with SSS Goal: to construct triangle ABC with sides AB=6cm, AC=5cm, and BC is equal to 4cm 6cm Step 1: Draw line AB which is 6cm long A B Step 2: Set the compass so the pencil and the compass point are 5cm apart Step 3: Place the Compass on point A and draw an arc 5cm Constructing Triangles with SSS Step 4: Now, set the compass and pencil so that they are 4cm apart. Step 5: Place the compass point on B and draw an arc so the lines insert. The point where the arcs insert, label it C Step 6: Draw segments AC and BC to complete the triangle, and label each segments with its length Constructing Triangles with AAA Goal: Draw a triangle that has the following degrees: <A 100 degrees, < B45 degrees and <C 35 degrees Step 1: Draw a tentative baseline (this means you will probably erase some of the line after all your angles are drawn) Step 2:Label the first point with A A Step 3: At point A, measure 100 degrees with your protractor, make a dot at 100 degrees and mark your dot with B B Step 4: Connect points A and point B A Constructing Triangles with AAA Step 5: From point B, measure 45 degrees with your protractor, and mark that point with a dot and label it C, connect B and C Connect point A and C to form your triangle Constructing a Parallelogram Goal: To construct a parallelogram BACD where AD=BC=5cm, BA=DC=2cm, Angle ABC=120 degrees, and angle BDC=60 degrees Step 1: Use a ruler to draw a line segment that is 5cm long B 5cm C HINT: Since BC is 5cm, what’s AC? Step 2: At point B, measure and mark 120 degrees. Draw segment BA 2cm long in the direction of 120 degrees. 2cm 120 degrees 5cm Constructing a Parallelogram Step 3: Use a protractor to measure 60 degrees at point C, and draw a line segment that is 2cm long A C 120 degrees B 60 degrees D Step 4: Draw line segment AD to complete the parallelogram 5cm A C 2cm 2cm B D Task... A triangle where... - PQ=6cm, QR=8cm, PR=10cm - All sides of CDE are 65mm HFG=50 degrees, =60 degrees, =70 degree • A quadrilateral where... - <C=110 degrees, <D=130 degrees, <F=50 degrees