Geometry

Triangles

• Triangle angle sum theorem: the sum of the angles in any triangle is 180°

• Triangle inequality theorem: the sum of the lengths of any two sides of a triangle is greater than the length of the third side.

Is this possible

• To draw a triangle with sides measuring 2cm, 3 cm, and 6 cm? (explain)

• To construct a triangle with angles measuring 30°, 50°, and 100°

Angles

• Adjacent angles: two angles that have a common side and a common vertex

• Vertical angles: two angles opposite one another when lines intersect. (vertical angles are congruent)

• Supplementary angles: two angles whose measures add to 180°

• Complementary angles: two angles whose measures add to 90°

Surface Area

• Surface area of a three dimensional figure is the sum of the areas of all of its surfaces.

• Find the area of each of the faces then add them to find the total.

• Independent practice p.34 ws.

Volume

• Volume of a three-dimensional figure is the number of cubic units that fit inside it.

• You can also use formulas to find volume.

• Practice p.38 and 39 ws.