An Introduction to 2-D Shape

1. An Introduction to 2-D Shape Slideshow 15, Mathematics Mr Richard Sasaki Room 307

2. Objectives • Recall names of certain elements of basic shapes • Recall formulae to find attributes to certain basic shapes • Apply these formulae to finding missing values for shapes

3. 2-D Shapes Square Triangle Rectangle (Oblong) Parallelogram Circle

4. The Square All lengths are equal and edges meet at 90o. (length)2 Area (A) = A = 2 =

5. The Rectangle Parallel sides are equal in length and edges meet at 90o. Area (A) = length × width A = = =

6. The Triangle Depending on type, triangles have three differing lengths and angles. Area (A) = ½ × base × height A = = =

7. The Circle A circle has 1 curved side (the circumference) or infinite sides of minute length. Circumference (C) = C = = Area (A) = A = r =

8. The Parallelogram A parallelogram has two pairs of parallel sides and two pairs of equal angles. Area (A) = base × height A = This will now be given to you on an information sheet. = =

9. Example An isosceles triangle has base 4cm and height 10cm. Calculate the area. Let’s label the values given on the triangle. A = That’s it for your easy example, try the worksheets! A = A =

10. Answers or an angle)

11. Answers , base: 4km