मराठी

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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प्रश्न

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

पर्याय

  • True

  • False

MCQ
चूक किंवा बरोबर
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उत्तर

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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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 9: Areas of Parallelograms & Triangles - Exercise 9.2 [पृष्ठ ८८]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 9
पाठ 9 Areas of Parallelograms & Triangles
Exercise 9.2 | Q 1. | पृष्ठ ८८

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

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Show that the diagonals of a parallelogram divide it into four triangles of equal area.


XY is a line parallel to side BC of a triangle ABC. If BE || AC and CF || AB meet XY at E and F respectively, show that

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