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In the given figure, ABCDE is a pentagon. A line through B parallel to AC meets DC produced at F. Show that - Mathematics

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प्रश्न

In the given figure, ABCDE is a pentagon. A line through B parallel to AC meets DC produced at F. Show that

(i) ar (ACB) = ar (ACF)

(ii) ar (AEDF) = ar (ABCDE)

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उत्तर

(i) ΔACB and ΔACF lie on the same base AC and are between

The same parallels AC and BF.

∴ Area (ΔACB) = Area (ΔACF)

 

(ii) It can be observed that

Area (ΔACB) = Area (ΔACF)

⇒ Area (ΔACB) + Area (ACDE) = Area (ACF) + Area (ACDE)

⇒ Area (ABCDE) = Area (AEDF)

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अध्याय 9: Areas of Parallelograms and Triangles - Exercise 9.3 [पृष्ठ १६३]

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एनसीईआरटी Mathematics [English] Class 9
अध्याय 9 Areas of Parallelograms and Triangles
Exercise 9.3 | Q 11 | पृष्ठ १६३

वीडियो ट्यूटोरियलVIEW ALL [1]

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ar (DBC) = ar (EBC). Prove that DE || BC.


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In the following figure, ABC and BDE are two equilateral triangles such that D is the mid-point of BC. If AE intersects BC at F, show that

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