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Ex 11.2, 4 - Find the missing values - Area of triangle - Class 7

Ex 11.2, 4 - Chapter 11 Class 7 Perimeter and Area - Part 2
Ex 11.2, 4 - Chapter 11 Class 7 Perimeter and Area - Part 3 Ex 11.2, 4 - Chapter 11 Class 7 Perimeter and Area - Part 4 Ex 11.2, 4 - Chapter 11 Class 7 Perimeter and Area - Part 5 Ex 11.2, 4 - Chapter 11 Class 7 Perimeter and Area - Part 6 Ex 11.2, 4 - Chapter 11 Class 7 Perimeter and Area - Part 7 Ex 11.2, 4 - Chapter 11 Class 7 Perimeter and Area - Part 8

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Transcript

Ex 11.2, 4 Find the missing values: (a) Base = 15 cm, Height = ?, Area = 87 cm2 Height = h = ? Base = b = 15 cm Given, Area of ∆ABC = 87 cm2 1/2 × b × h = 87 1/2 × 15 × h = 87 h = 87 × 2/15 h = 29 × 2/5 h = 58/5 h = 11.6 cm ∴ Height is 11.6 cm (a) Base = ?, Height = 31.4 mm, Area = 1256 mm2 Height = h = 31.4 mm Base = b = ? Given, Area of ∆ABC = 1256 mm2 1/2 × b × h = 1256 1/2 × b × 31.4 = 1256 b = 1256 × 2/31.4 b = 1256 × 2 × 1/31.4 b = 1256 × 2 × 10/(314 ) b = 1256 × 10/157 b = 1256/157 × 10 b = 8 × 10 b = 80 mm (a) Base = 22 cm, Height = ?, Area = 170.5 cm2 Height = h = ? Base = b = 22 cm Given, Area of ∆ABC = 170.5 cm2 1/2 × b × h = 170.5 1/2 × 22 × h = 170.5 11 × h = 170.5 h = 170.5/11 h = 1705/(11 × 10) h = 155/10 h = 15.5 cm ∴ Height is 15.5 cm

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Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 13 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.