In fig 6.52, the area of ∆ ABC (in square units) is

(A) 15 

(B) 10

(C) 7.5 

(D) 2.5

This question is similar to Example 11 - Chapter 7 Class 10 Coordinate Geometry

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Transcript

Question 2 In fig 6.52, the area of ∆ ABC (in square units) is (A) 15 (B) 10 (C) 7.5 (D) 2.5 Vertices of triangle are A(1, 3), B(-1, 0) and C(4, 0) Here x1 = 1 , y1 = 3 x2 = −1 , y2 = 0 x3 = 4 , y3 = 0 Now, Area of triangle = 1/2 [ x1(y2 – y3) + x2(y3 – y1) + x3(y1 – y2) ] = 1/2 [ 1(0 – 0) + (−1)(0 – 3) + 4(3 – 0)] = 1/2 [ 1 × 0 + (−1) × (– 3) + 4 × 3 ] = 1/2 [ 0 + 3 + 12 ] = 1/2 × 15 = 7.5 square units So, the correct answer is (C)

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Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.