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Area and Perimeter. Yes you do need to write this. AREA. The amount of space inside a 2-dimensional object. Measured in square units cm 2 , m 2 , mm 2 Not to be confused with……. Perimeter. The distance around a two dimensional object.
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Area and Perimeter Yes you do need to write this.
AREA • The amount of space inside a 2-dimensional object. • Measured in square units cm2, m2, mm2 • Not to be confused with……
Perimeter • The distance around a two dimensional object. • Measured in ‘normal’ units eg. cm, m, mm
Some shapes have there own formulas for area Yes, you do need to draw these as well.
b a Area of a rectangle = ab (length x width) Perimeter = 2a + 2b = 2(a + b) Rectangle
a b ‘a’ is the vertical height Parallelogram – quadrilateral with two pairs of parallel sides. Area = ab Can not work out the perimeter with the information given. Parallelogram
6cm 7cm Area = 6 x 7 =42 cm2 One to try
a h b Add together the parallel sides, divide by 2 and then multiply by the distance between them. Area = (a + b) x h 2 Trapezium(a quadrilateral with one pair of parallel sides)
2cm 10cm 5cm Area = (2 + 5) x 10 2 = 3.5 x 10 = 35 cm2 Example
Compound Shapes • These are shapes made by joining two or more shapes together. • To find the area, find the area of the smaller shapes and add together.
7cm 10cm 8cm 3cm 7cm 2cm 8cm 3cm Example. X Y
Example. Area of X = 7 x 2 = 14 cm2 Area of Y = 3 x 8 = 24 cm2 Total area = 14 + 24 = 38 cm2 7cm 2cm 8cm 3cm X Y
10cm 10cm Area of square = 10 x 10 = 100 cm2 A. of triangle = ½ x 3 x 4 = 6 cm2 Shaded area = 100 – 6 = 94 cm2 Last one.Find the shaded area 3cm 3cm 4cm
The only part left is circles(always a circle question) And then it’s volume.