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The ratio of the lengths of corresponding sides in similar figures (same shape but different size) is called scale factor. It may be expressed as a fraction, decimal, percent, or whole number.
The scale factor from Fig A to Fig B is 3/6 = ½. The scale factor from Fig B to Fig A is 6/3 = 2 6 cm 3 cm Fig A Fig B 45 square centimeters 32 square centimeters Since area is measured in square units, the scale factor needs to be squared before multiplying it by the area of the first shape to find the area of the dilation. Our original shape is 3 cm by 5 cm. Therefore the area is 3 x 5 or 15 square centimeters. A similar shape dilated with a scale factor of 3 will have an area of... 5 3 90 square centimeters 135 square centimeters 5(3) 3(3) If the original area of a shape is 32 square centimeters and is dilated by a scale factor of ¼, the new shape's area would be... 8 8 2 square cm 4 square cm 32 square cm 64 square cm 8(¼) 8(¼) The area of a rectangle is 12 inches squared. The rectangle is dilated by a scale factor of ½. What is the area of the new rectangle? inches squared The area of a square is 64 square inches. The square is dilated by a scale factor of 2. What is the area of the new square? square inches Figure A is dilated creating Fig B.
What is the scale factor from Fig A to Fig B?
What is the perimeter of Fig B?
What is the area of Fig B? Fig A 9 9 Fig B square units 3 units 3 Figure A is dilated creating Fig B.
What is the scale factor from Fig A to Fig B?
What is the area of Fig A?
What is the area of Fig B? Fig A 3 3 Fig B square units square units 9 9 A rectangle is dilated with a scale factor of 3. Which statement correctly describes the area of the new figure? The new area is 1/9 times the original The new area is 1/3 times the original The new area is 3 times the original The new area is 9 times the original A rectangle is dilated with a scale factor of ⅓. Which statement correctly describes the area of the new figure? The new area is 1/9 times the original The new area is 1/3 times the original The new area is 3 times the original The new area is 9 times the original |