This post is about finding ratio of areas for 2 figures. These types of questions often comes out in Emaths Vectors, Similar figures questions like this question shown.
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Follow these 3 rules to solve these types of questions.
- Check if the 2 figures shares a common height. Then proceed to write out the formulae of their area leaving the common height unknown in the fraction. The unknown height will be cancelled out in the fraction.
Examples:
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2. Check if the figures are similar. For similar figures, apply this formulae. A1/A2 = (l1/l2)square
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3. Check if the 2 figures shares a common area. Then proceed to form fraction expressions of the 3 different areas. Lastly, form an equation to get the ratio of the 2 areas asked in the question.
This last type of question needs some practice and students will get the concept to solve them in no time. 🙂
