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ABCD is a parallelogram and X is the mid-point of AB. If ar (AXCD) = 24 cm2, then ar (ABC) = 24 cm2. - Mathematics

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Question

ABCD is a parallelogram and X is the mid-point of AB. If ar (AXCD) = 24 cm2, then ar (ABC) = 24 cm2.

Options

  • True

  • False

MCQ
True or False
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Solution

This statement is False.

Explanation:

Given in the question, ABCD is a parallelogram and X is the mid-point of AB.

So, area(ABCD) = area(AXCD) + area(ΔXBC)  ...(i)

Now, diagonal AC of a parallelogram divides it into two triangles of equal area.

area(ABCD) = 2area(ΔABC)  ...(ii)

Similarly, X is the mid-point of AB,

So, area(ΔCXB) = `1/2`area(ΔABC)   ...(iii) [Median divides the triangle in two triangles of equal area]

2area(ΔABC) = `24 + 1/2` area(ΔABC)  ...[By using equation (i), (ii) and (iii)]

Now, 2area(ΔABC) – `1/2`area(ΔABC) = 24

`3/2`area(ΔABC) = 24

Therefore, area(ΔABC) = `(2 xx 24)/3` = 16 cm2.

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Chapter 9: Areas of Parallelograms & Triangles - Exercise 9.2 [Page 88]

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NCERT Exemplar Mathematics [English] Class 9
Chapter 9 Areas of Parallelograms & Triangles
Exercise 9.2 | Q 1. | Page 88

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