Chapter+9+Notes



Questions to complete for 9B - Q 1,2,3,5,10,11,15 (worked solutions provided)

This video will help you identify triangles that are similar

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This video will help you work through problems... Watch it :)

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For 9C we can use similarity to work out the area and volume of prisms, triangles, spheres etc. Since area is uses two dimensions if for example we doubled the radius of a circle. The area would increase by a factor of (2^2 = 4). So if there are two circles, one with a radius of 2 cm and the other which a radius of 6cm. As 6cm radius is 3 times larger, the area of the circle has increased by a factor of (3^2 = 9). In the case of volume a sphere is proportional to the radius cubed. Therefore 2 spheres that are similar, if we where to double the dimensions then the volume would increase by a factor of (2^3 = 8). So by doubling the radius of a sphere we have increased the volume by a factor of 8.... This should be revision for some of you as it is part of the year 10 mathematics curriculum.

Questions to complete for 9C - Q 1,3,4,9,10,14,17,21 (worked solutions provided)