Learn about scale factors and similar figures. Grade 9 Alberta mathematics geometry lesson.
Lesson 7.1 of Similarity & Transformations in Grade 9 Math: Alberta curriculum lessons.
Before working with scale diagrams, both numbers must be in the same units. You can't compare centimetres to metres or kilometres to millimetres, always convert first
Examples:
A scale diagram is a drawing that shows an object's shape in proportion to its real size. It allows us to represent large or small objects conveniently on paper, like buildings, vehicles, or maps.
Enlargements are bigger than the original diagram, so the scale factor must be greater than 1.
Reductions are smaller than the original diagram, so the scale factor must be less than 1.
A top view of a patio table is 105 cm by 165 cm. A reduction is to be drawn with scale factor of 1/3. Determine the dimensions of the reduction.
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