Question 1 - Figure it out - Page 157-159 - Chapter 7 Class 8 - Area (Ganita Prakash II)

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Question 1 (i) Find the areas of the following triangles:Here, AE ⊥ BC So, we can write Height = AE = h = 3 cm Base = BC = b = 4 cm Area of ∆ABC = 1/2 × Base × Height = 1/2 × BC × AE = 𝟏/𝟐 × 4 × 3 = 2 × 3 = 6 cm2 Question 1 (ii) Find the areas of the following triangles:Here, DN ⊥ EF So, we can write Height = DN = h = 3.2 cm Base = EF = b = 5 cm Area of ∆DEF = 1/2 × Base × Height = 1/2 × EF × DN = 𝟏/𝟐 × 5 × 3.2 = 1/2 × 5 × 32/10 = 5 × 16/10 = 80/10 = 8 cm2 Question 1 (iii) Find the areas of the following triangles:This is a right angled triangle where AN ⊥ AT So, we can consider AN as base, AT as height Or AT as base, AN as height Let’s consider this Height = AN = h = 4 cm Base = AT = b = 3 cm Area of ∆ANT = 1/2 × Base × Height = 1/2 × AT × AN = 𝟏/𝟐 × 3 × 4 = 3 × 2 = 6 cm2