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A point E is taken on the side BC of a parallelogram ABCD. AE and DC are produced to meet at F. Prove that ar (ADF) = ar (ABFC)

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प्रश्न

A point E is taken on the side BC of a parallelogram ABCD. AE and DC are produced to meet at F. Prove that ar (ADF) = ar (ABFC)

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उत्तर

Given in the question, A point E is taken on the side BC of a parallelogram ABCD. AE and DC are produced to meet at F.

Prove that ar (ADF) = ar (ABFC)

Proof: ABCD is a parallelogram and AC divides it into two triangle of equal area.

ar (ΔADC) = ar (ΔABC)   ...(I)

So, DC || AB and CF || AB

As we know that triangle on the same base and between the same parallels are equal in area.

So, ar (ΔACF) = ar (ΔBCF)  ...(II)

Adding equation (I) and (II), we get

ar (ΔADC) + ar (ACF) = ar (ΔABC) + ar (ΔBCF)

ar (ΔADF) = ar (ABFC)

Hence proved.

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अध्याय 9: Areas of Parallelograms & Triangles - Exercise 9.4 [पृष्ठ ९४]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 9
अध्याय 9 Areas of Parallelograms & Triangles
Exercise 9.4 | Q 1. | पृष्ठ ९४

वीडियो ट्यूटोरियलVIEW ALL [1]

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